Powered surgical cutting and stapling apparatus with manually retractable firing system

ABSTRACT

In one general aspect, various embodiments of the present invention can include a motorized surgical cutting and fastening instrument having a drive shaft, a motor selectively engageable with the drive shaft, and a manual return mechanism configured to operably disengage the motor from the drive shaft and retract the drive shaft. In at least one embodiment, a surgeon, or other operator of the surgical instrument, can utilize the manual return mechanism to retract the drive shaft after it has been advanced, especially when the motor, or a power source supplying the motor, has failed or is otherwise unable to provide a force sufficient to retract the drive shaft.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 15/054,751, entitledPOWERED SURGICAL CUTTING AND STAPLING APPARATUS WITH MANUALLYRETRACTABLE FIRING SYSTEM, filed Feb. 26, 2016, now U.S. PatentApplication Publication No. 2016/0174984, which is a continuationapplication claiming priority under 35 U.S.C. § 120 to U.S. patentapplication Ser. No. 13/785,432, entitled POWERED SURGICAL CUTTING ANDSTAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM, filed Mar.5, 2013, which issued on Jun. 21, 2016 as U.S. Pat. No. 9,370,364, whichis a continuation application claiming priority under 35 U.S.C. § 120 toU.S. patent application Ser. No. 12/249,117, entitled POWERED SURGICALCUTTING AND STAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM,filed on Oct. 10, 2008, which issued on Dec. 17, 2013 as U.S. Pat. No.8,608,045, the entire disclosures of which are hereby incorporated byreference herein.

BACKGROUND 1. Field of the Invention

The present invention generally concerns surgical cutting and fasteninginstruments and, more particularly, motor-driven surgical cutting andfastening instruments.

2. Description of the Related Art

Endoscopic surgical instruments are often preferred over traditionalopen surgical devices since a smaller incision, or incisions, associatedwith endoscopic surgical techniques tends to reduce the post-operativerecovery time and complications. Consequently, significant developmenthas gone into a range of endoscopic surgical instruments that aresuitable for precise placement of a distal end effector at a desiredsurgical site through a cannula of a trocar. These distal end effectorsengage the tissue in a number of ways to achieve a diagnostic ortherapeutic effect (e.g., endocutter, grasper, cutter, staplers, clipapplier, access device, drug/gene therapy delivery device, and energydevice using ultrasound, RF, laser, etc.).

Known surgical staplers include an end effector that simultaneouslymakes a longitudinal incision in tissue and applies lines of staples onopposing sides of the incision. The end effector includes a pair ofcooperating jaw members that, if the instrument is intended forendoscopic or laparoscopic applications, are capable of passing througha cannula passageway. One of the jaw members receives a staple cartridgehaving at least two laterally spaced rows of staples. The other jawmember defines an anvil having staple-forming pockets aligned with therows of staples in the cartridge. The instrument includes a plurality ofmovable wedges which, when driven distally, pass through openings in thestaple cartridge and engage drivers supporting the staples to effect thefiring of the staples toward the anvil.

An example of a surgical stapler suitable for endoscopic applications isdescribed in U.S. Pat. No. 5,465,895, the disclosure of which is herebyincorporated by reference in its entirety, which discloses an endocutterwith distinct closing and firing actions. A clinician using this deviceis able to close the jaw members upon tissue to position the tissueprior to firing. Once the clinician has determined that the jaw membersare properly gripping tissue, the clinician can then fire the surgicalstapler with a single firing stroke, or multiple firing strokes,depending on the device. Firing the surgical stapler causes severing andstapling of the tissue. The simultaneous severing and stapling avoidscomplications that may arise when performing such actions sequentiallywith different surgical tools that respectively only sever or staple.

SUMMARY

In one general aspect, various embodiments of the present invention caninclude a motorized surgical cutting and fastening instrument having adrive shaft, a motor selectively engageable with the drive shaft, and amanual return mechanism configured to retract the drive shaft andoperably disengage the motor from the drive shaft. In at least oneembodiment, a surgeon, or other operator of the surgical instrument, canutilize the manual return mechanism to retract the drive shaft after ithas been advanced, especially when the motor, or a power sourcesupplying the motor, has failed or is otherwise unable to provide aforce sufficient to retract the drive shaft. In various embodiments, theoperation of the manual return mechanism can operably disconnect themotor from the drive shaft via mechanical, electrical, electronic,and/or electro-mechanical arrangements, for example.

In at least one embodiment, the instrument can include an end effectorcomprising a movable cutting member for cutting an object positioned inthe end effector, wherein the drive shaft can be operably coupled withthe cutting member and can be movable between a proximal position and adistal position. In at least one such embodiment, the drive shaft caninclude a plurality of first drive teeth and a plurality of second driveteeth, wherein the instrument can further include a pinion gearselectively engageable with the plurality of first drive teeth, a motorconfigured to rotate the pinion gear, and a firing trigger configuredsuch that the operation of the firing trigger actuates the motor.

In at least one embodiment, the instrument can further include a pivot,a lever rotatable about the pivot in a first direction and a seconddirection, a cam, wherein the lever is configured to move the cambetween a first position and a second position, and a pinion springconfigured to bias the pinion gear into operative engagement with thedrive shaft when the cam is in its first position. In variousembodiments, the cam can be configured to engage the pinion gear whenthe cam is moved from its first position to its second position and movethe pinion gear away from the drive shaft such that the pinion gear isoperably disengaged from the plurality of first drive teeth.

In at least one embodiment, the instrument can further include a pawlrotatably mounted to the lever and a pawl spring operably engaged withthe pawl, wherein the pawl spring can be configured to move the pawlbetween a disengaged position in which the pawl is operably disengagedfrom the plurality of second drive teeth and an engaged position inwhich the pawl is operably engaged with the plurality of second driveteeth. In various embodiments, the pawl spring can move the pawl betweenits disengaged and engaged positions when the cam is moved from itsfirst position to its second position. Once the pawl is in its engagedposition, the pawl can be configured to move the drive shaft from itsdistal position toward its proximal position when the lever is rotatedin the first direction. The pawl can also be configured to slide overthe plurality of second teeth when the lever is rotated in the seconddirection.

This Summary is intended be briefly outline certain embodiments of thesubject application. It should be understood that the subjectapplication is not limited to the embodiments disclosed in this Summary,and is intended to cover modifications that are within its spirit andscope, as defined by the claims. It should be further understood thatthis Summary should not be read or construed in a manner that will actto narrow the scope of the claims.

BRIEF DESCRIPTION OF THE FIGURES

Various embodiments of the present invention are described herein by wayof example in conjunction with the following figures, wherein

FIGS. 1 and 2 are perspective views of a surgical cutting and fasteninginstrument;

FIGS. 3-5 are exploded views of an end effector and shaft of theinstrument of FIG. 1;

FIG. 6 is a side view of the end effector according of FIG. 3;

FIG. 7 is an exploded view of the handle of the instrument of FIG. 1;

FIGS. 8 and 9 are partial perspective views of the handle of FIG. 7;

FIG. 10 is a side view of the handle of FIG. 7;

FIG. 11 is a schematic diagram of a circuit used in the instrumentaccording to various embodiments;

FIGS. 12-13 are side views of the handle according to other embodiments;

FIGS. 14-22 illustrate different mechanisms for locking the closuretrigger according to various embodiments;

FIGS. 23A-B show a universal joint (“u-joint”) that may be employed atthe articulation point of the instrument;

FIGS. 24A-B shows a torsion cable that may be employed at thearticulation point of the instrument;

FIGS. 25-31 illustrate a surgical cutting and fastening instrument withpower assist according to various embodiments;

FIGS. 32-36 illustrate a surgical cutting and fastening instrument withpower assist according to yet other various embodiments;

FIGS. 37-40 illustrate a surgical cutting and fastening instrument withtactile feedback according to various embodiments;

FIGS. 41-42 illustrate a proportional sensor that may be used accordingto various embodiments;

FIG. 43 is a perspective view of a drive shaft and a manual returnmechanism of a surgical cutting and fastening instrument according tovarious embodiments of the present invention;

FIG. 44 is an exploded view of the drive shaft and the manual returnmechanism of the surgical cutting and fastening instrument of FIG. 43;

FIG. 45 is another perspective view of the drive shaft and the manualreturn mechanism of FIG. 43;

FIG. 46 is an elevational view of the drive shaft and the manual returnmechanism of FIG. 43;

FIG. 47 is a partial cut-away view of the manual return mechanism ofFIG. 43 and an electric motor operably engaged with the drive shaft;

FIG. 48 is another partial cut-away view of the manual return mechanismof FIG. 43 illustrating a lever, a cam in a first position, and a pawlpivotably mounted to the lever where the pawl is being held in adisengaged position;

FIG. 49 is another partial cut-away view of the manual return mechanismof FIG. 43 illustrating the lever rotated in a first direction, the camnearly in a second position, and the pawl on the verge of being movedinto an engaged position with the drive shaft by a pawl spring;

FIG. 50 is another partial cut-away view of the manual return mechanismof FIG. 43 illustrating the lever rotated in a second direction which isopposite the first direction, the cam still in its second position, andthe pawl being slid along a plurality of teeth on the drive shaft;

FIG. 51 is another partial cut-away view of the manual return mechanismof FIG. 43 illustrating the lever rotated in the first direction onceagain, the cam still in its second position, and the pawl being used toretract the drive shaft;

FIG. 52 is an exploded view of an end effector in accordance with anembodiment of the present invention, the end effector including a knifebar configured to be operably coupled with the drive shaft of FIG. 43;

FIG. 53 is a cut-away view of the end-effector of FIG. 52;

FIG. 54 is a diagram of a drive shaft and a manual return mechanism of asurgical cutting and fastening instrument according to alternativeembodiments of the present invention illustrating an electric motoroperably engaged with a drive shaft;

FIG. 55 is another diagram of the surgical instrument of FIG. 54illustrating the manual return mechanism operably engaged with the driveshaft and the electric motor operably disengaged from the drive shaft;

FIG. 56 is a diagram of a rotatable drive shaft and a manual returnmechanism of a surgical cutting and fastening instrument according tovarious embodiments of the present invention, the diagram illustrating apinion gear operably engaged with a gear box and a motor via a drivegear;

FIG. 57 is a diagram of the manual return mechanism of FIG. 56illustrating a yoke disengaged from the pinion gear in order to allow apinion gear spring to bias the pinion gear into engagement with a leverof the manual return mechanism and, in addition, bias the pinion gearout of engagement with the drive gear, the diagram further illustratingthe lever in a starting position;

FIG. 58 is a diagram of the manual return mechanism of FIG. 56illustrating the lever being ratcheted back into its starting positionand the pinion gear partially engaged with the drive gear;

FIG. 59 is an end view of the yoke and pinion gear of FIG. 57;

FIG. 60 is a schematic diagram of a circuit including a switchconfigured to be actuated by the lever of the manual retractionmechanism of FIG. 56, wherein the actuation of the switch operablydisengages the motor;

FIG. 61 is a perspective view of a drive shaft and a manual returnmechanism of a surgical cutting and fastening instrument according tovarious embodiments of the present invention, the diagram illustrating apinion gear rotatably supported by a swing arm wherein the pinion gearis operably engaged with a motor and the drive shaft;

FIG. 62 is a partial cut-away view of the manual return mechanism ofFIG. 61;

FIG. 63 is a partial cut-away view of the manual return mechanism ofFIG. 61 illustrating a lever rotated in a first direction in order todisengage the lever from the swing arm and allow a spring to bias thepinion gear and the swing arm away from the drive shaft;

FIG. 64 is a top view of the drive shaft and the manual return mechanismof FIG. 61 illustrating the pinion gear engaged with the drive shaft andthe motor;

FIG. 65 is a top view of the drive shaft and the manual return mechanismof FIG. 61 illustrating the pinion gear disengaged from the drive shaftand the motor;

FIG. 66 is a partial cut-away view of the drive shaft and the manualreturn mechanism of FIG. 61 illustrating the pinion gear engaged withthe drive shaft and the motor; and

FIG. 67 is a partial cut-away view of the drive shaft and the manualreturn mechanism of FIG. 61 illustrating the pinion gear disengaged fromthe drive shaft and the motor.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate preferred embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

Preferred embodiments of the presently disclosed endoscopic surgicalstapling apparatus will now be described in detail with reference to thedrawings, in which like reference numerals designate identical orcorresponding elements in each of the several views. Those of ordinaryskill in the art will understand that the devices and methodsspecifically described herein and illustrated in the accompanyingdrawings are non-limiting exemplary embodiments and that the scope ofthe various embodiments of the present invention is defined solely bythe claims. The features illustrated or described in connection with oneexemplary embodiment may be combined with the features of otherembodiments. Such modifications and variations are intended to beincluded within the scope of the present invention.

FIGS. 1 and 2 depict a surgical cutting and fastening instrument 10. Theillustrated embodiment is an endoscopic instrument and, in general, theembodiments of the instrument 10 described herein are endoscopicsurgical cutting and fastening instruments. It should be noted, however,that according to various embodiments of the present invention, theinstrument may be a non-endoscopic surgical cutting and fasteninginstrument, such as a laparoscopic instrument, for example. Varioussurgical instruments are disclosed in U.S. patent application Ser. No.10/674,026, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING AMULTISTROKE FIRING POSITION INDICATOR WITH RETRACTION MECHANISM, filedon Sep. 29, 2003, now U.S. Pat. No. 7,364,061; U.S. patent applicationSer. No. 11/343,498, entitled MOTOR-DRIVEN SURGICAL CUTTING ANDFASTENING INSTRUMENT WITH USER FEEDBACK SYSTEM, filed on Jan. 31, 2006,now U.S. Pat. No. 7,766,210; and U.S. patent application Ser. No.11/497,936, entitled PNEUMATICALLY POWERED SURGICAL CUTTING ANDFASTENING INSTRUMENT WITH MANUALLY OPERATED RETRACTION APPARATUS, filedon Aug. 2, 2006, now U.S. Pat. No. 7,448,525, the entire disclosures ofwhich are incorporated herein by reference.

The surgical instrument 10 depicted in FIGS. 1 and 2 comprises a handle6, a shaft 8, and an articulating end effector 12 pivotally connected tothe shaft 8 at an articulation pivot 14. An articulation control 16 maybe provided adjacent to the handle 6 to effect rotation of the endeffector 12 about the articulation pivot 14. In the illustratedembodiment, the end effector 12 is configured to act as an endocutterfor clamping, severing and stapling tissue, although, in otherembodiments, different types of end effectors may be used, such as endeffectors for other types of surgical devices, such as graspers,cutters, staplers, clip appliers, access devices, drug/gene therapydevices, ultrasound, RF or laser devices, etc.

The handle 6 of the instrument 10 may include a closure trigger 18 and afiring trigger 20 for actuating the end effector 12. It will beappreciated that instruments having end effectors directed to differentsurgical tasks may have different numbers or types of triggers or othersuitable controls for operating the end effector 12. The end effector 12is shown separated from the handle 6 by a preferably elongate shaft 8.In one embodiment, a clinician or operator of the instrument 10 mayarticulate the end effector 12 relative to the shaft 8 by utilizing thearticulation control 16, as described in more detail in U.S. patentapplication Ser. No. 11/329,020, filed Jan. 10, 2006, entitled SURGICALINSTRUMENT HAVING AN ARTICULATING END EFFECTOR, now U.S. Pat. No.7,670,334, the entire disclosure of which is incorporated herein byreference.

The end effector 12 includes in this example, among other things, astaple channel 22 and a pivotally translatable clamping member, such asan anvil 24, which are maintained at a spacing that assures effectivestapling and severing of tissue clamped in the end effector 12. Thehandle 6 includes a pistol grip 26 towards which a closure trigger 18 ispivotally drawn by the clinician to cause clamping or closing of theanvil 24 toward the staple channel 22 of the end effector 12 to therebyclamp tissue positioned between the anvil 24 and channel 22. The firingtrigger 20 is farther outboard of the closure trigger 18. Once theclosure trigger 18 is locked in the closure position as furtherdescribed below, the firing trigger 20 may rotate slightly toward thepistol grip 26 so that it can be reached by the operator using one hand.Then the operator may pivotally draw the firing trigger 20 toward thepistol grip 12 to cause the stapling and severing of clamped tissue inthe end effector 12. In other embodiments, different types of clampingmembers besides the anvil 24 could be used, such as, for example, anopposing jaw, etc.

It will be appreciated that the terms “proximal” and “distal” are usedherein with reference to a clinician gripping the handle 6 of aninstrument 10. Thus, the end effector 12 is distal with respect to themore proximal handle 6. It will be further appreciated that, forconvenience and clarity, spatial terms such as “vertical” and“horizontal” are used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and absolute.

The closure trigger 18 may be actuated first. Once the clinician issatisfied with the positioning of the end effector 12, the clinician maydraw back the closure trigger 18 to its fully closed, locked positionproximate to the pistol grip 26. The firing trigger 20 may then beactuated. The firing trigger 20 returns to the open position (shown inFIGS. 1 and 2) when the clinician removes pressure, as described morefully below. A release button on the handle 6, when depressed mayrelease the locked closure trigger 18. The release button may beimplemented in various forms such as, for example, as a slide releasebutton 160 shown in FIG. 14, and/or button 172 shown in FIG. 16.

FIG. 3 is an exploded view of the end effector 12 according to variousembodiments. As shown in the illustrated embodiment, the end effector 12may include, in addition to the previously-mentioned channel 22 andanvil 24, a cutting instrument 32, a sled 33, a staple cartridge 34 thatis removably seated in the channel 22, and a helical screw shaft 36. Thecutting instrument 32 may be, for example, a knife. The anvil 24 may bepivotably opened and closed at a pivot point 25 connected to theproximate end of the channel 22. The anvil 24 may also include a tab 27at its proximate end that is inserted into a component of the mechanicalclosure system (described further below) to open and close the anvil 24.When the closure trigger 18 is actuated, that is, drawn in by a user ofthe instrument 10, the anvil 24 may pivot about the pivot point 25 intothe clamped or closed position. If clamping of the end effector 12 issatisfactory, the operator may actuate the firing trigger 20, which, asexplained in more detail below, causes the knife 32 and sled 33 totravel longitudinally along the channel 22, thereby cutting tissueclamped within the end effector 12. The movement of the sled 33 alongthe channel 22 causes the staples of the staple cartridge 34 to bedriven through the severed tissue and against the closed anvil 24, whichturns the staples to fasten the severed tissue. In various embodiments,the sled 33 may be an integral component of the cartridge 34. U.S. Pat.No. 6,978,921, entitled SURGICAL STAPLING INSTRUMENT INCORPORATING ANE-BEAM FIRING MECHANISM, filed on May 20, 2003, the entire disclosure ofwhich is incorporated herein by reference, provides more details aboutsuch two-stroke cutting and fastening instruments. The sled 33 may bepart of the cartridge 34, such that when the knife 32 retracts followingthe cutting operation, the sled 33 does not retract.

It should be noted that although the embodiments of the instrument 10described herein employ an end effector 12 that staples the severedtissue, in other embodiments different techniques for fastening orsealing the severed tissue may be used. For example, end effectors thatuse RF energy or adhesives to fasten the severed tissue may also beused. U.S. Pat. No. 5,709,680 entitled ELECTROSURGICAL HEMOSTATICDEVICE, filed on Dec. 22, 1994; and U.S. Pat. No. 5,688,270 entitledELECTROSURGICAL HEMOSTATIC DEVICE WITH RECESSED AND/OR OFFSETELECTRODES, filed on Jan. 18, 1995, the entire disclosures of which areincorporated herein by reference, disclose an endoscopic cuttinginstrument that uses RF energy to seal the severed tissue. U.S. patentapplication Ser. No. 11/267,811 entitled SURGICAL STAPLING INSTRUMENTSSTRUCTURED FOR DELIVERY OF MEDICAL AGENTS, filed on Nov. 4, 2005, nowU.S. Pat. No. 7,673,783; and U.S. patent application Ser. No. 11/267,383entitled SURGICAL STAPLING INSTRUMENTS STRUCTURED FOR PUMP-ASSISTEDDELIVERY OF MEDICAL AGENTS, filed on Nov. 4, 2005, now U.S. Pat. No.7,607,557, the entire disclosures of which are also incorporated hereinby reference, disclose an endoscopic cutting instrument that usesadhesives to fasten the severed tissue. Accordingly, although thedescription herein refers to cutting/stapling operations and the likebelow, it should be recognized that this is an exemplary embodiment andis not meant to be limiting. Other tissue-fastening techniques may alsobe used.

FIGS. 4 and 5 are exploded views and FIG. 6 is a side view of the endeffector 12 and shaft 8 according to various embodiments. As shown inthe illustrated embodiment, the shaft 8 may include a proximate closuretube 40 and a distal closure tube 42 pivotably linked by a pivot links44. The distal closure tube 42 includes an opening 45 into which the tab27 on the anvil 24 is inserted in order to open and close the anvil 24,as further described below. Disposed inside the closure tubes 40, 42 maybe a proximate spine tube 46. Disposed inside the proximate spine tube46 may be a main rotational (or proximate) drive shaft 48 thatcommunicates with a secondary (or distal) drive shaft 50 via a bevelgear assembly 52. The secondary drive shaft 50 is connected to a drivegear 54 that engages a proximate drive gear 56 of the helical screwshaft 36. The vertical bevel gear 52 b may sit and pivot in an opening57 in the distal end of the proximate spine tube 46. A distal spine tube58 may be used to enclose the secondary drive shaft 50 and the drivegears 54, 56. Collectively, the main drive shaft 48, the secondary driveshaft 50, and the articulation assembly (e.g., the bevel gear assembly52 a-c) are sometimes referred to herein as the “main drive shaftassembly.”

A bearing 38, positioned at a distal end of the staple channel 22,receives the helical drive screw 36, allowing the helical drive screw 36to freely rotate with respect to the channel 22. The helical screw shaft36 may interface a threaded opening (not shown) of the knife 32 suchthat rotation of the shaft 36 causes the knife 32 to translate distallyor proximately (depending on the direction of the rotation) through thestaple channel 22. Accordingly, when the main drive shaft 48 is causedto rotate by actuation of the firing trigger 20 (as explained in moredetail below), the bevel gear assembly 52 a-c causes the secondary driveshaft 50 to rotate, which in turn, because of the engagement of thedrive gears 54, 56, causes the helical screw shaft 36 to rotate, whichcauses the knife driving member 32 to travel longitudinally along thechannel 22 to cut any tissue clamped within the end effector. The sled33 may be made of, for example, plastic, and may have a sloped distalsurface. As the sled 33 traverse the channel 22, the sloped forwardsurface may push up or drive the staples in the staple cartridge throughthe clamped tissue and against the anvil 24. The anvil 24 turns thestaples, thereby stapling the severed tissue. When the knife 32 isretracted, the knife 32 and sled 33 may become disengaged, therebyleaving the sled 33 at the distal end of the channel 22.

FIGS. 7-10 illustrate an exemplary embodiment of a motor-drivenendocutter, and in particular the handle thereof, that providesuser-feedback regarding the deployment and loading force of the cuttinginstrument in the end effector. In addition, the embodiment may usepower provided by the user in retracting the firing trigger 20 to powerthe device (a so-called “power assist” mode). As shown in theillustrated embodiment, the handle 6 includes exterior lower side pieces59, 60 and exterior upper side pieces 61, 62 that fit together to form,in general, the exterior of the handle 6. A battery 64, such as a Li ionbattery, may be provided in the pistol grip portion 26 of the handle 6.In some embodiments, the battery may comprise a LiMnO2 and/or NiCdbattery, for example. In certain embodiments, the battery may beexternal to pistol grip portion 26 and/or the surgical instrumentaltogether, for example. The battery 64 powers a motor 65 disposed in anupper portion of the pistol grip portion 26 of the handle 6. Accordingto various embodiments, the motor 65 may be a DC brushed driving motorhaving a maximum rotation of, approximately, 5000 RPM, for example. Incertain embodiments, the rotation can be approximately 20000 RPM, forexample, less than 20000, greater 20000, and/or suitable speed for therequired load and/or operational parameters. The motor 64 may drive a90° bevel gear assembly 66 comprising a first bevel gear 68 and a secondbevel gear 70. The bevel gear assembly 66 may drive a planetary gearassembly 72. The planetary gear assembly 72 may include a pinion gear 74connected to a drive shaft 76. The pinion gear 74 may drive a matinggear 78 that drives a helical gear drum 80 via a drive shaft 82. A ring84 may be threaded on the helical gear drum 80. Thus, when the motor 65rotates, the ring 84 is caused to travel along the helical gear drum 80by means of the interposed bevel gear assembly 66, planetary gearassembly 72 and gear 78.

The handle 6 may also include a run motor sensor 110 in communicationwith the firing trigger 20 to detect when the firing trigger 20 has beendrawn in (or “closed”) toward the pistol grip portion 26 of the handle 6by the operator to thereby actuate the cutting/stapling operation by theend effector 12. The sensor 110 may be a proportional sensor such as,for example, a rheostat, variable resistor, and/or limit switch. Whenthe firing trigger 20 is drawn in, the sensor 110 detects the movement,and sends an electrical signal indicative of the voltage (or power) tobe supplied to the motor 65. When the sensor 110 is a variable resistoror the like, the rotation of the motor 65 may be generally proportionalto the amount of movement of the firing trigger 20. That is, if theoperator only draws or closes the firing trigger 20 in a little bit, therotation of the motor 65 is relatively low. When the firing trigger 20is fully drawn in (or in the fully closed position), the rotation of themotor 65 is at its maximum. In other words, the harder the user pulls onthe firing trigger 20, the more voltage is applied to the motor 65,causing greater rates of rotation.

The handle 6 may include a middle handle piece 104 adjacent to the upperportion of the firing trigger 20. The handle 6 also may comprise a biasspring 112 connected between posts on the middle handle piece 104 andthe firing trigger 20. The bias spring 112 may bias the firing trigger20 to its fully open position. In that way, when the operator releasesthe firing trigger 20, the bias spring 112 will pull the firing trigger20 to its open position, thereby removing actuation of the sensor 110,thereby stopping rotation of the motor 65. Moreover, by virtue of thebias spring 112, any time a user closes the firing trigger 20, the userwill experience resistance to the closing operation, thereby providingthe user with feedback as to the amount of rotation exerted by the motor65. Further, the operator could stop retracting the firing trigger 20 tothereby remove force from the sensor 100, to thereby stop the motor 65.As such, the user may stop the deployment of the end effector 12,thereby providing a measure of control of the cutting/fasteningoperation to the operator.

The distal end of the helical gear drum 80 includes a distal drive shaft120 that drives a gear 122, which mates with a pinion gear 124. Thepinion gear 124 is connected to the main drive shaft 48 of the maindrive shaft assembly. In that way, rotation of the motor 65 causes themain drive shaft assembly to rotate, which causes actuation of the endeffector 12, as described above.

The ring 84 threaded on the helical gear drum 80 may include a post 86that is disposed within a slot 88 of a slotted arm 90. The slotted arm90 has an opening 92 its opposite end 94 that receives a pivot pin 96that is connected between the handle exterior side pieces 59, 60. Thepivot pin 96 is also disposed through an opening 100 in the firingtrigger 20 and an opening 102 in the middle handle piece 104.

In addition, the handle 6 may include a reverse motor (or end-of-strokesensor) 130 and a stop motor (or beginning-of-stroke) sensor 142. Invarious embodiments, the reverse motor sensor 130 may be a limit switchlocated at the distal end of the helical gear drum 80 such that the ring84 threaded on the helical gear drum 80 contacts and trips the reversemotor sensor 130 when the ring 84 reaches the distal end of the helicalgear drum 80. The reverse motor sensor 130, when activated, sends asignal to the motor 65 to reverse its rotation direction, therebywithdrawing the knife 32 of the end effector 12 following the cuttingoperation.

The stop motor sensor 142 may be, for example, a normally-closed limitswitch. In various embodiments, it may be located at the proximate endof the helical gear drum 80 so that the ring 84 trips the switch 142when the ring 84 reaches the proximate end of the helical gear drum 80.

In operation, when an operator of the instrument 10 pulls back thefiring trigger 20, the sensor 110 detects the deployment of the firingtrigger 20 and sends a signal to the motor 65 to cause forward rotationof the motor 65 at, for example, a rate proportional to how hard theoperator pulls back the firing trigger 20. The forward rotation of themotor 65 in turn causes the gear 78 at the distal end of the planetarygear assembly 72 to rotate, thereby causing the helical gear drum 80 torotate, causing the ring 84 threaded on the helical gear drum 80 totravel distally along the helical gear drum 80. The rotation of thehelical gear drum 80 also drives the main drive shaft assembly asdescribed above, which in turn causes deployment of the knife 32 in theend effector 12. That is, the knife 32 and sled 33 are caused totraverse the channel 22 longitudinally, thereby cutting tissue clampedin the end effector 12. Also, the stapling operation of the end effector12 is caused to happen in embodiments where a stapling-type end effectoris used.

By the time the cutting/stapling operation of the end effector 12 iscomplete, the ring 84 on the helical gear drum 80 will have reached thedistal end of the helical gear drum 80, thereby causing the reversemotor sensor 130 to be tripped, which sends a signal to the motor 65 tocause the motor 65 to reverse its rotation. This in turn causes theknife 32 to retract, and also causes the ring 84 on the helical geardrum 80 to move back to the proximate end of the helical gear drum 80.

The middle handle piece 104 includes a backside shoulder 106 thatengages the slotted arm 90 as best shown in FIGS. 8 and 9. The middlehandle piece 104 also has a forward motion stop 107 that engages thefiring trigger 20. The movement of the slotted arm 90 is controlled, asexplained above, by rotation of the motor 65. When the slotted arm 90rotates CCW as the ring 84 travels from the proximate end of the helicalgear drum 80 to the distal end, the middle handle piece 104 will be freeto rotate CCW. Thus, as the user draws in the firing trigger 20, thefiring trigger 20 will engage the forward motion stop 107 of the middlehandle piece 104, causing the middle handle piece 104 to rotate CCW. Dueto the backside shoulder 106 engaging the slotted arm 90, however, themiddle handle piece 104 will only be able to rotate CCW as far as theslotted arm 90 permits. In that way, if the motor 65 should stoprotating for some reason, the slotted arm 90 will stop rotating, and theuser will not be able to further draw in the firing trigger 20 becausethe middle handle piece 104 will not be free to rotate CCW due to theslotted arm 90.

FIGS. 41 and 42 illustrate two states of a variable sensor that may beused as the run motor sensor 110. The sensor 110 may include a faceportion 280, a first electrode (A) 282, a second electrode (B) 284, anda compressible dielectric material 286 (e.g., EAP) between theelectrodes 282, 284. The sensor 110 may be positioned such that the faceportion 280 contacts the firing trigger 20 when retracted. Accordingly,when the firing trigger 20 is retracted, the dielectric material 286 iscompressed, as shown in FIG. 42, such that the electrodes 282, 284 arecloser together. Since the distance “b” between the electrodes 282, 284is directly related to the impedance between the electrodes 282, 284,the greater the distance the more impedance, and the closer the distancethe less impedance. In that way, the amount that the dielectric 286 iscompressed due to retraction of the firing trigger 20 (denoted as force“F” in FIG. 42) is proportional to the impedance between the electrodes282, 284, which can be used to proportionally control the motor 65.

Components of an exemplary closure system for closing (or clamping) theanvil 24 of the end effector 12 by retracting the closure trigger 18 arealso shown in FIGS. 7-10. In the illustrated embodiment, the closuresystem includes a yoke 250 connected to the closure trigger 18 by a pin251 that is inserted through aligned openings in both the closuretrigger 18 and the yoke 250. A pivot pin 252, about which the closuretrigger 18 pivots, is inserted through another opening in the closuretrigger 18 which is offset from where the pin 251 is inserted throughthe closure trigger 18. Thus, retraction of the closure trigger 18causes the upper part of the closure trigger 18, to which the yoke 250is attached via the pin 251, to rotate CCW. The distal end of the yoke250 is connected, via a pin 254, to a first closure bracket 256. Thefirst closure bracket 256 connects to a second closure bracket 258.Collectively, the closure brackets 256, 258 define an opening in whichthe proximate end of the proximate closure tube 40 (see FIG. 4) isseated and held such that longitudinal movement of the closure brackets256, 258 causes longitudinal motion by the proximate closure tube 40.The instrument 10 also includes a closure rod 260 disposed inside theproximate closure tube 40. The closure rod 260 may include a window 261into which a post 263 on one of the handle exterior pieces, such asexterior lower side piece 59 in the illustrated embodiment, is disposedto fixedly connect the closure rod 260 to the handle 6. In that way, theproximate closure tube 40 is capable of moving longitudinally relativeto the closure rod 260. The closure rod 260 may also include a distalcollar 267 that fits into a cavity 269 in proximate spine tube 46 and isretained therein by a cap 271 (see FIG. 4).

In operation, when the yoke 250 rotates due to retraction of the closuretrigger 18, the closure brackets 256, 258 cause the proximate closuretube 40 to move distally (i.e., away from the handle end of theinstrument 10), which causes the distal closure tube 42 to movedistally, which causes the anvil 24 to rotate about the pivot point 25into the clamped or closed position. When the closure trigger 18 isunlocked from the locked position, the proximate closure tube 40 iscaused to slide proximately, which causes the distal closure tube 42 toslide proximately, which, by virtue of the tab 27 being inserted in thewindow 45 of the distal closure tube 42, causes the anvil 24 to pivotabout the pivot point 25 into the open or unclamped position. In thatway, by retracting and locking the closure trigger 18, an operator mayclamp tissue between the anvil 24 and channel 22, and may unclamp thetissue following the cutting/stapling operation by unlocking the closuretrigger 20 from the locked position.

FIG. 11 is a schematic diagram of an electrical circuit of theinstrument 10. When an operator initially pulls in the firing trigger 20after locking the closure trigger 18, the sensor 110 is activated,allowing current to flow there through. If the normally-open reversemotor sensor switch 130 is open (meaning the end of the end effectorstroke has not been reached), current may flow to a single pole, doublethrow relay 132. Since the reverse motor sensor switch 130 is notclosed, the inductor 134 of the relay 132 may not be energized, so therelay 132 will be in its non-energized state. In certain embodiments,current may be reversed via a switch, such as a single pole, doublethrow switch, for example. In at least one embodiment, the motor may bereversed without the use of a relay at all. The circuit also includes acartridge lockout sensor 136. If the end effector 12 includes a staplecartridge 34, the sensor 136 will be in the closed state, allowingcurrent to flow. Otherwise, if the end effector 12 does not include astaple cartridge 34, the sensor 136 will be open, thereby preventing thebattery 64 from powering the motor 65.

When the staple cartridge 34 is present, the sensor 136 is closed, whichenergizes a single pole, single throw relay 138. When the relay 138 isenergized, current flows through the relay 136, through the variableresistor sensor 110, and to the motor 65 via a double pole, double throwrelay 140, thereby powering the motor 65 and allowing it to rotate inthe forward direction.

When the end effector 12 reaches the end of its stroke, the reversemotor sensor 130 will be activated, thereby closing the switch 130 andenergizing the relay 134. This causes the relay 134 to assume itsenergized state (not shown in FIG. 13), which causes current to bypassthe cartridge lockout sensor 136 and variable resistor 110, and insteadcauses current to flow to both the normally-closed double pole, doublethrow relay 142 and back to the motor 65, but in a manner, via the relay140, that causes the motor 65 to reverse its rotational direction.

Because the stop motor sensor switch 142 is normally-closed, currentwill flow back to the relay 134 to keep it closed until the switch 142opens. When the knife 32 is fully retracted, the stop motor sensorswitch 142 is activated, causing the switch 142 to open, therebyremoving power from the motor 65.

In other embodiments, rather than a proportional-type sensor 110, anon-off type sensor could be used. In such embodiments, the rate ofrotation of the motor 65 would not be proportional to the force appliedby the operator. Rather, the motor 65 would generally rotate at aconstant rate. But the operator would still experience force feedbackbecause the firing trigger 20 is geared into the gear drive train.

FIG. 12 is a side-view of the handle 6 of a power-assist motorizedendocutter according to another embodiment. The embodiment of FIG. 12 issimilar to that of FIGS. 7-10 except that in the embodiment of FIG. 12,there is not a slotted arm connected to the ring 84 threaded on thehelical gear drum 80. Instead, in the embodiment of FIG. 12, the ring 84includes a sensor portion 114 that moves with the ring 84 as the ring 84advances down (and back) on the helical gear drum 80. The sensor portion114 includes a notch 116. The reverse motor sensor 130 may be located atthe distal end of the notch 116 and the stop motor sensor 142 may belocated at the proximate end of the notch 116. As the ring 84 moves downthe helical gear drum 80 (and back), the sensor portion 114 moves withit. Further, as shown in FIG. 12, the middle piece 104 may have an arm118 that extends into the notch 12.

In operation, as an operator of the instrument 10 retracts in the firingtrigger 20 toward the pistol grip 26, the run motor sensor 110 detectsthe motion and sends a signal to power the motor 65, which causes, amongother things, the helical gear drum 80 to rotate. As the helical geardrum 80 rotates, the ring 84 threaded on the helical gear drum 80advances (or retracts, depending on the rotation). Also, due to thepulling in of the firing trigger 20, the middle piece 104 is caused torotate CCW with the firing trigger 20 due to the forward motion stop 107that engages the firing trigger 20. The CCW rotation of the middle piece104 cause the arm 118 to rotate CCW with the sensor portion 114 of thering 84 such that the arm 118 stays disposed in the notch 116. When thering 84 reaches the distal end of the helical gear drum 80, the arm 118will contact and thereby trip the reverse motor sensor 130. Similarly,when the ring 84 reaches the proximate end of the helical gear drum 80,the arm will contact and thereby trip the stop motor sensor 142. Suchactions may reverse and stop the motor 65, respectively, as describedabove.

FIG. 13 is a side-view of the handle 6 of a power-assist motorizedendocutter according to another embodiment. The embodiment of FIG. 13 issimilar to that of FIGS. 7-10 except that in the embodiment of FIG. 13,there is no slot in the arm 90. Instead, the ring 84 threaded on thehelical gear drum 80 includes a vertical channel 126. Instead of a slot,the arm 90 includes a post 128 that is disposed in the channel 126. Asthe helical gear drum 80 rotates, the ring 84 threaded on the helicalgear drum 80 advances (or retracts, depending on the rotation). The arm90 rotates CCW as the ring 84 advances due to the post 128 beingdisposed in the channel 126, as shown in FIG. 13.

As mentioned above, in using a two-stroke motorized instrument, theoperator first pulls back and locks the closure trigger 18. FIGS. 14 and15 show one embodiment of a way to lock the closure trigger 18 to thepistol grip portion 26 of the handle 6. In the illustrated embodiment,the pistol grip portion 26 includes a hook 150 that is biased to rotateCCW about a pivot point 151 by a torsion spring 152. Also, the closuretrigger 18 includes a closure bar 154. As the operator draws in theclosure trigger 18, the closure bar 154 engages a sloped portion 156 ofthe hook 150, thereby rotating the hook 150 upward (or CW in FIGS.12-13) until the closure bar 154 completely passes the sloped portion156 passes into a recessed notch 158 of the hook 150, which locks theclosure trigger 18 in place. The operator may release the closuretrigger 18 by pushing down on a slide button release 160 on the back oropposite side of the pistol grip portion 26. Pushing down the slidebutton release 160 rotates the hook 150 CW such that the closure bar 154is released from the recessed notch 158.

FIG. 16 shows another closure trigger locking mechanism according tovarious embodiments. In the embodiment of FIG. 16, the closure trigger18 includes a wedge 160 having an arrow-head portion 161. The arrow-headportion 161 is biased downward (or CW) by a leaf spring 162. The wedge160 and leaf spring 162 may be made from, for example, molded plastic.When the closure trigger 18 is retracted, the arrow-head portion 161 isinserted through an opening 164 in the pistol grip portion 26 of thehandle 6. A lower chamfered surface 166 of the arrow-head portion 161engages a lower sidewall 168 of the opening 164, forcing the arrow-headportion 161 to rotate CCW. Eventually the lower chamfered surface 166fully passes the lower sidewall 168, removing the CCW force on thearrow-head portion 161, causing the lower sidewall 168 to slip into alocked position in a notch 170 behind the arrow-head portion 161.

To unlock the closure trigger 18, a user presses down on a button 172 onthe opposite side of the closure trigger 18, causing the arrow-headportion 161 to rotate CCW and allowing the arrow-head portion 161 toslide out of the opening 164.

FIGS. 17-22 show a closure trigger locking mechanism according toanother embodiment. As shown in this embodiment, the closure trigger 18includes a flexible longitudinal arm 176 that includes a lateral pin 178extending therefrom. The arm 176 and pin 178 may be made from moldedplastic, for example. The pistol grip portion 26 of the handle 6includes an opening 180 with a laterally extending wedge 182 disposedtherein. When the closure trigger 18 is retracted, the pin 178 engagesthe wedge 182, and the pin 178 is forced downward (i.e., the arm 176 isrotated CW) by the lower surface 184 of the wedge 182, as shown in FIGS.17 and 18. When the pin 178 fully passes the lower surface 184, the CWforce on the arm 176 is removed, and the pin 178 is rotated CCW suchthat the pin 178 comes to rest in a notch 186 behind the wedge 182, asshown in FIG. 19, thereby locking the closure trigger 18. The pin 178 isfurther held in place in the locked position by a flexible stop 188extending from the wedge 184.

To unlock the closure trigger 18, the operator may further squeeze theclosure trigger 18, causing the pin 178 to engage a sloped backwall 190of the opening 180, forcing the pin 178 upward past the flexible stop188, as shown in FIGS. 20 and 21. The pin 178 is then free to travel outan upper channel 192 in the opening 180 such that the closure trigger 18is no longer locked to the pistol grip portion 26, as shown in FIG. 22.

FIGS. 23A-B show a universal joint (“u-joint”) 195. The second piece195-2 of the u-joint 195 rotates in a horizontal plane in which thefirst piece 195-1 lies. FIG. 23A shows the u-joint 195 in a linear(180°) orientation and FIG. 23B shows the u-joint 195 at approximately a150° orientation. The u-joint 195 may be used instead of the bevel gears52 a-c (see FIG. 4, for example) at the articulation point 14 of themain drive shaft assembly to articulate the end effector 12. FIGS. 24A-Bshow a torsion cable 197 that may be used in lieu of both the bevelgears 52 a-c and the u-joint 195 to realize articulation of the endeffector 12.

FIGS. 25-31 illustrate another embodiment of a motorized, two-strokesurgical cutting and fastening instrument 10 with power assist. Theembodiment of FIGS. 25-31 is similar to that of FIGS. 6-10 except thatinstead of the helical gear drum 80, the embodiment of FIGS. 23-28includes an alternative gear drive assembly. The embodiment of FIGS.25-31 includes a gear box assembly 200 including a number of gearsdisposed in a frame 201, wherein the gears are connected between theplanetary gear 72 and the pinion gear 124 at the proximate end of thedrive shaft 48. As explained further below, the gear box assembly 200provides feedback to the user via the firing trigger 20 regarding thedeployment and loading force of the end effector 12. Also, the user mayprovide power to the system via the gear box assembly 200 to assist thedeployment of the end effector 12. In that sense, like the embodimentsdescribed above, the embodiment of FIGS. 23-32 is another power assist,motorized instrument 10 that provides feedback to the user regarding theloading force experienced by the cutting instrument.

In the illustrated embodiment, the firing trigger 20 includes twopieces: a main body portion 202 and a stiffening portion 204. The mainbody portion 202 may be made of plastic, for example, and the stiffeningportion 204 may be made out of a more rigid material, such as metal. Inthe illustrated embodiment, the stiffening portion 204 is adjacent tothe main body portion 202, but according to other embodiments, thestiffening portion 204 could be disposed inside the main body portion202. A pivot pin 209 may be inserted through openings in the firingtrigger pieces 202, 204 and may be the point about which the firingtrigger 20 rotates. In addition, a spring 222 may bias the firingtrigger 20 to rotate in a CCW direction. The spring 222 may have adistal end connected to a pin 224 that is connected to the pieces 202,204 of the firing trigger 20. The proximate end of the spring 222 may beconnected to one of the handle exterior lower side pieces 59, 60.

In the illustrated embodiment, both the main body portion 202 and thestiffening portion 204 includes gear portions 206, 208 (respectively) attheir upper end portions. The gear portions 206, 208 engage a gear inthe gear box assembly 200, as explained below, to drive the main driveshaft assembly and to provide feedback to the user regarding thedeployment of the end effector 12.

The gear box assembly 200 may include as shown, in the illustratedembodiment, six (6) gears. A first gear 210 of the gear box assembly 200engages the gear portions 206, 208 of the firing trigger 20. Inaddition, the first gear 210 engages a smaller second gear 212, thesmaller second gear 212 being coaxial with a large third gear 214. Thethird gear 214 engages a smaller fourth gear 216, the smaller fourthgear being coaxial with a fifth gear 218. The fifth gear 218 is a 90°bevel gear that engages a mating 90° bevel gear 220 (best shown in FIG.31) that is connected to the pinion gear 124 that drives the main driveshaft 48.

In operation, when the user retracts the firing trigger 20, a run motorsensor (not shown) is activated, which may provide a signal to the motor65 to rotate at a rate proportional to the extent or force with whichthe operator is retracting the firing trigger 20. This causes the motor65 to rotate at a speed proportional to the signal from the sensor. Thesensor is not shown for this embodiment, but it could be similar to therun motor sensor 110 described above. The sensor could be located in thehandle 6 such that it is depressed when the firing trigger 20 isretracted. Also, instead of a proportional-type sensor, an on/off typesensor may be used.

Rotation of the motor 65 causes the bevel gears 66, 70 to rotate, whichcauses the planetary gear 72 to rotate, which causes, via the driveshaft 76, the gear 122 to rotate. The gear 122 meshes with the piniongear 124, which is connected to the main drive shaft 48. Thus, rotationof the pinion gear 124 drives the main drive shaft 48, which causesactuation of the cutting/stapling operation of the end effector 12.

Forward rotation of the pinion gear 124 in turn causes the bevel gear220 to rotate, which causes, by way of the rest of the gears of the gearbox assembly 200, the first gear 210 to rotate. The first gear 210engages the gear portions 206, 208 of the firing trigger 20, therebycausing the firing trigger 20 to rotate CCW when the motor 65 providesforward drive for the end effector 12 (and to rotate CCW when the motor65 rotates in reverse to retract the end effector 12). In that way, theuser experiences feedback regarding loading force and deployment of theend effector 12 by way of the user's grip on the firing trigger 20.Thus, when the user retracts the firing trigger 20, the operator willexperience a resistance related to the load force experienced by the endeffector 12. Similarly, when the operator releases the firing trigger 20after the cutting/stapling operation so that it can return to itsoriginal position, the user will experience a CW rotation force from thefiring trigger 20 that is generally proportional to the reverse speed ofthe motor 65.

It should also be noted that in this embodiment the user can apply force(either in lieu of or in addition to the force from the motor 65) toactuate the main drive shaft assembly (and hence the cutting/staplingoperation of the end effector 12) through retracting the firing trigger20. That is, retracting the firing trigger 20 causes the gear portions206, 208 to rotate CCW, which causes the gears of the gear box assembly200 to rotate, thereby causing the pinion gear 124 to rotate, whichcauses the main drive shaft 48 to rotate.

Although not shown in FIGS. 25-31, the instrument 10 may further includereverse motor and stop motor sensors. As described above, the reversemotor and stop motor sensors may detect, respectively, the end of thecutting stroke (full deployment of the knife/sled driving member 32) andthe end of retraction operation (full retraction of the knife/sleddriving member 32). A similar circuit to that described above inconnection with FIG. 11 may be used to appropriately power the motor 65.

FIGS. 32-36 illustrate a two-stroke, motorized surgical cutting andfastening instrument 10 with power assist according to anotherembodiment. The embodiment of FIGS. 32-36 is similar to that of FIGS.25-31 except that in the embodiment of FIGS. 32-36, the firing trigger20 includes a lower portion 228 and an upper portion 230. Both portions228, 230 are connected to and pivot about a pivot pin 207 that isdisposed through each portion 228, 230. The upper portion 230 includes agear portion 232 that engages the first gear 210 of the gear boxassembly 200. The spring 222 is connected to the upper portion 230 suchthat the upper portion is biased to rotate in the CW direction. Theupper portion 230 may also include a lower arm 234 that contacts anupper surface of the lower portion 228 of the firing trigger 20 suchthat when the upper portion 230 is caused to rotate CW the lower portion228 also rotates CW, and when the lower portion 228 rotates CCW theupper portion 230 also rotates CCW. Similarly, the lower portion 228includes a rotational stop 238 that engages a lower shoulder of theupper portion 230. In that way, when the upper portion 230 is caused torotate CCW the lower portion 228 also rotates CCW, and when the lowerportion 228 rotates CW the upper portion 230 also rotates CW.

The illustrated embodiment also includes the run motor sensor 110 thatcommunicates a signal to the motor 65 that, in various embodiments, maycause the motor 65 to rotate at a speed proportional to the forceapplied by the operator when retracting the firing trigger 20. Thesensor 110 may be, for example, a rheostat or some other variableresistance sensor, as explained herein. In addition, the instrument 10may include a reverse motor sensor 130 that is tripped or switched whencontacted by a front face 242 of the upper portion 230 of the firingtrigger 20. When activated, the reverse motor sensor 130 sends a signalto the motor 65 to reverse direction. Also, the instrument 10 mayinclude a stop motor sensor 142 that is tripped or actuated whencontacted by the lower portion 228 of the firing trigger 20. Whenactivated, the stop motor sensor 142 sends a signal to stop the reverserotation of the motor 65.

In operation, when an operator retracts the closure trigger 18 into thelocked position, the firing trigger 20 is retracted slightly (throughmechanisms known in the art, including U.S. Pat. No. 6,978,921 entitledSURGICAL STAPLING INSTRUMENT INCORPORATING AN E-BEAM FIRING MECHANISM,filed on May 20, 2003, and U.S. Pat. No. 6,905,057 entitled SURGICALSTAPLING INSTRUMENT INCORPORATING A FIRING MECHANISM HAVING A LINKEDRACK TRANSMISSION, filed on Sep. 29, 2003, the entire disclosures ofwhich are incorporated herein by reference, so that the user can graspthe firing trigger 20 to initiate the cutting/stapling operation, asshown in FIGS. 32 and 33. At that point, as shown in FIG. 33, the gearportion 232 of the upper portion 230 of the firing trigger 20 moves intoengagement with the first gear 210 of the gear box assembly 200. Whenthe operator retracts the firing trigger 20, according to variousembodiments, the firing trigger 20 may rotate a small amount, such asfive degrees, before tripping the run motor sensor 110, as shown in FIG.34. Activation of the sensor 110 causes the motor 65 to forward rotateat a rate proportional to the retraction force applied by the operator.The forward rotation of the motor 65 causes, as described above, themain drive shaft 48 to rotate, which causes the knife 32 in the endeffector 12 to be deployed (i.e., begin traversing the channel 22).Rotation of the pinion gear 124, which is connected to the main driveshaft 48, causes the gears 210-220 in the gear box assembly 200 torotate. Since the first gear 210 is in engagement with the gear portion232 of the upper portion 230 of the firing trigger 20, the upper portion232 is caused to rotate CCW, which causes the lower portion 228 to alsorotate CCW.

When the knife 32 is fully deployed (i.e., at the end of the cuttingstroke), the front face 242 of the upper portion 230 trips the reversemotor sensor 130, which sends a signal to the motor 65 to reverserotational directional. This causes the main drive shaft assembly toreverse rotational direction to retract the knife 32. Reverse rotationof the main drive shaft assembly causes the gears 210-220 in the gearbox assembly to reverse direction, which causes the upper portion 230 ofthe firing trigger 20 to rotate CW, which causes the lower portion 228of the firing trigger 20 to rotate CW until the lower portion 228 tripsor actuates the stop motor sensor 142 when the knife 32 is fullyretracted, which causes the motor 65 to stop. In that way, the userexperiences feedback regarding deployment of the end effector 12 by wayof the user's grip on the firing trigger 20. Thus, when the userretracts the firing trigger 20, the operator will experience aresistance related to the deployment of the end effector 12 and, inparticular, to the loading force experienced by the knife 32. Similarly,when the operator releases the firing trigger 20 after thecutting/stapling operation so that it can return to its originalposition, the user will experience a CW rotation force from the firingtrigger 20 that is generally proportional to the reverse speed of themotor 65.

It should also be noted that in this embodiment the user can apply force(either in lieu of or in addition to the force from the motor 65) toactuate the main drive shaft assembly (and hence the cutting/staplingoperation of the end effector 12) through retracting the firing trigger20. That is, retracting the firing trigger 20 causes the gear portion232 of the upper portion 230 to rotate CCW, which causes the gears ofthe gear box assembly 200 to rotate, thereby causing the pinion gear 124to rotate, which causes the main drive shaft assembly to rotate.

The above-described embodiments employed power-assist user feedbacksystems, with or without adaptive control (e.g., using a sensor 110,130, and 142 outside of the closed loop system of the motor, gear drivetrain, and end effector) for a two-stroke, motorized surgical cuttingand fastening instrument. That is, force applied by the user inretracting the firing trigger 20 may be added to the force applied bythe motor 65 by virtue of the firing trigger 20 being geared into(either directly or indirectly) the gear drive train between the motor65 and the main drive shaft 48. In other embodiments, the user may beprovided with tactile feedback regarding the position of the knife 32 inthe end effector, but without having the firing trigger 20 geared intothe gear drive train. FIGS. 37-40 illustrate a motorized surgicalcutting and fastening instrument with such a tactile position feedbacksystem.

In the illustrated embodiment of FIGS. 37-40, the firing trigger 20 mayhave a lower portion 228 and an upper portion 230, similar to theinstrument 10 shown in FIGS. 32-36. Unlike the embodiment of FIGS.32-36, however, the upper portion 230 does not have a gear portion thatmates with part of the gear drive train. Instead, the instrumentincludes a second motor 265 with a threaded rod 266 threaded therein.The threaded rod 266 reciprocates longitudinally in and out of the motor265 as the motor 265 rotates, depending on the direction of rotation.The instrument 10 also includes an encoder 268 that is responsive to therotations of the main drive shaft 48 for translating the incrementalangular motion of the main drive shaft 48 (or other component of themain drive assembly) into a corresponding series of digital signals, forexample. In the illustrated embodiment, the pinion gear 124 includes aproximate drive shaft 270 that connects to the encoder 268.

The instrument 10 also includes a control circuit (not shown), which maybe implemented using a microcontroller or some other type of integratedcircuit, that receives the digital signals from the encoder 268. Basedon the signals from the encoder 268, the control circuit may calculatethe stage of deployment of the knife 32 in the end effector 12. That is,the control circuit can calculate if the knife 32 is fully deployed,fully retracted, or at an intermittent stage. Based on the calculationof the stage of deployment of the end effector 12, the control circuitmay send a signal to the second motor 265 to control its rotation tothereby control the reciprocating movement of the threaded rod 266.

In operation, as shown in FIG. 37, when the closure trigger 18 is notlocked into the clamped position, the firing trigger 20 rotated awayfrom the pistol grip portion 26 of the handle 6 such that the front face242 of the upper portion 230 of the firing trigger 20 is not in contactwith the proximate end of the threaded rod 266. When the operatorretracts the closure trigger 18 and locks it in the clamped position,the firing trigger 20 rotates slightly towards the closure trigger 20 sothat the operator can grasp the firing trigger 20, as shown in FIG. 38.In this position, the front face 242 of the upper portion 230 contactsthe proximate end of the threaded rod 266.

As the user then retracts the firing trigger 20, after an initialrotational amount (e.g., 5 degrees of rotation) the run motor sensor 110may be activated such that, as explained above, the sensor 110 sends asignal to the motor 65 to cause it to rotate at a forward speedproportional to the amount of retraction force applied by the operatorto the firing trigger 20. Forward rotation of the motor 65 causes themain drive shaft 48 to rotate via the gear drive train, which causes theknife 32 and sled 33 to travel down the channel 22 and sever tissueclamped in the end effector 12. The control circuit receives the outputsignals from the encoder 268 regarding the incremental rotations of themain drive shaft assembly and sends a signal to the second motor 265 tocaused the second motor 265 to rotate, which causes the threaded rod 266to retract into the motor 265. This allows the upper portion 230 of thefiring trigger 20 to rotate CCW, which allows the lower portion 228 ofthe firing trigger to also rotate CCW. In that way, because thereciprocating movement of the threaded rod 266 is related to therotations of the main drive shaft assembly, the operator of theinstrument 10, by way of his/her grip on the firing trigger 20,experiences tactile feedback as to the position of the end effector 12.The retraction force applied by the operator, however, does not directlyaffect the drive of the main drive shaft assembly because the firingtrigger 20 is not geared into the gear drive train in this embodiment.

By virtue of tracking the incremental rotations of the main drive shaftassembly via the output signals from the encoder 268, the controlcircuit can calculate when the knife 32 is fully deployed (i.e., fullyextended). At this point, the control circuit may send a signal to themotor 65 to reverse direction to cause retraction of the knife 32. Thereverse direction of the motor 65 causes the rotation of the main driveshaft assembly to reverse direction, which is also detected by theencoder 268. Based on the reverse rotation detected by the encoder 268,the control circuit sends a signal to the second motor 265 to cause itto reverse rotational direction such that the threaded rod 266 starts toextend longitudinally from the motor 265. This motion forces the upperportion 230 of the firing trigger 20 to rotate CW, which causes thelower portion 228 to rotate CW. In that way, the operator may experiencea CW force from the firing trigger 20, which provides feedback to theoperator as to the retraction position of the knife 32 in the endeffector 12. The control circuit can determine when the knife 32 isfully retracted. At this point, the control circuit may send a signal tothe motor 65 to stop rotation.

According to other embodiments, rather than having the control circuitdetermine the position of the knife 32, reverse motor and stop motorsensors may be used, as described above. In addition, rather than usinga proportional sensor 110 to control the rotation of the motor 65, anon/off switch or sensor can be used. In such an embodiment, the operatorwould not be able to control the rate of rotation of the motor 65.Rather, it would rotate at a preprogrammed rate.

In various embodiments, as described above, a motor can be utilized toadvance a cutting member and/or staple-driving sled distally within anend effector of a surgical instrument. In at least one such embodiment,as also described above, the motor can be utilized to retract thecutting member and/or sled proximally. In some circumstances, however,the motor may be incapable of generating or supplying a sufficientforce, or torque, to retract the cutting member and/or sled. Suchcircumstances may arise when the motor becomes defective or when thecutting member becomes stuck within the end effector. Other suchcircumstances may arise when the battery, or other suitable powersource, supplying the motor cannot provide sufficient power to themotor. In any event, various embodiments of the present invention cancomprise a manual return system which can be utilized to retract thecutting member and/or sled, for example. In certain circumstances, suchmanual return systems can be referred to as “bail-out mechanisms”. Invarious embodiments, a manual return mechanism can be configured tooperably disengage, or disconnect, the motor from the cutting memberand/or sled at the same time, prior to, and/or after the manual returnmechanism is operably engaged with the cutting member and/or sled. In atleast one such embodiment, as a result, the cutting member and/or sledcan be retracted without interference from a broken motor and/or adysfunctional motor attempting to advance the cutting member and/orsled, for example.

In various embodiments, referring to FIG. 43, a surgical instrument,such as a surgical stapler, for example, can include a firing rod, ordrive shaft, 400 which can be advanced and/or retracted by a motor, suchas electrical motor 402 depicted in FIG. 47, for example. In at leastone such embodiment, referring again to FIG. 47, motor 402 can bemounted to, or mounted relative to, frame 404 such that there is no, orat least little, relative movement between frame 404 and motor housing401. Electrical motor 402 can be configured to receive electrical energysupplied thereto and convert at least a portion of such electricalenergy to mechanical energy. In at least one embodiment, electricalmotor 402 can be configured to rotate rod 406 and drive gear 408. Incertain embodiments, drive gear 408 can be integrally formed with rod406 or, alternatively, drive gear 408 can be sufficiently or fixedlyattached to rod 406 such that the rotation of rod 406 can be transmittedto drive gear 408. In at least one such embodiment, drive gear 408 caninclude an aperture therein which can be configured to receive rod 406in a press-fit relationship, for example. In various embodiments,although not illustrated in FIGS. 43-53, a surgical instrument caninclude a firing trigger, such as firing trigger 20 (FIG. 1), forexample, which, when actuated, can allow electrical current to flow tomotor 402 and supply motor 402 with electrical power. In certainembodiments, as described above, the surgical instrument can include abattery which can be placed in electrical communication with motor 402when the trigger is actuated.

In various embodiments, referring again to FIG. 47, drive gear 408 canbe operably engaged with pinion gear 410 such that the rotation of drivegear 408 can be transmitted to pinion gear 410. In at least one suchembodiment, pinion gear 410 can include teeth which can be meshinglyengaged with the teeth of drive gear 408. As illustrated in FIG. 44,pinion gear 410 can include an aperture 411 extending therethrough, orat least partially therethrough, which can be configured to receive pin412. In at least one such embodiment, although not illustrated, aperture411 and pin 412 can be sized and configured to permit pinion gear 410 torotate relative to pin 412 wherein aperture 411 can be configured toclosely receive pin 412 such that pin 412 can define an axis about whichpinion gear 410 can rotate. In various alternative embodiments,referring again to FIG. 47, pinion gear 410 can be integrally formedwith or fixedly mounted to pin 412 such that rotation of pinion gear 410is transmitted to pin 412. In at least one such embodiment, pin 412 canbe press-fit within aperture 411 of pinion gear 410. In certainembodiments, frame 404 can include apertures 414 and 416 which can eachbe configured to closely receive a portion of pin 412 such thatapertures 414 and 416 can define an axis about which pin 412, and piniongear 410, can rotate.

In certain embodiments, pin 412 can be slidably received withinapertures 414 and 416 such that, as described in greater detail below,pinion gear 410 can be selectively engaged and disengaged with driveshaft 400. For the present purposes, though, the arrangement of thesurgical instrument as depicted in FIG. 47 depicts pinion gear 410 inoperative engagement with drive shaft 400. The various circumstances inwhich pinion gear 410 may be operatively disengaged from drive shaft 400will be addressed further below. Referring primarily to FIGS. 43-47,pinion gear 410 can be operably engaged with drive shaft 400 such thatthe rotation of drive gear 408 can be transmitted to drive shaft 400. Inat least one embodiment, drive shaft 400 can include a first rackportion comprising a plurality of first drive teeth 418 which can beconfigured to be meshingly engaged with the teeth of pinion gear 410such that the rotation of pinion gear 410 can translate, or displace,drive shaft 400 along a predetermined path. For example, referring toFIGS. 43-47, pinion gear 410 can be configured to move shaft 400distally along axis 403 in a direction indicated by arrow D and/orproximally along axis 403 in a direction indicated by arrow P, dependingon the direction in which drive gear 408, and correspondingly piniongear 410, are rotated by motor 402. Although the predetermined path canbe linear, or at least substantially linear, other embodiments areenvisioned in which a drive shaft can be moved along a non-linear pathsuch as a curved, and/or curvi-linear, path, for example.

Referring to FIGS. 46 and 47, a surgical instrument can further includepinion spring 420 which can be configured to bias pinion gear 410 intooperative engagement with first drive teeth 418. In various embodiments,the frame 404 can include a pinion gear chamber 422 that can comprise,among other things, a first surface 424 and a second surface 426 betweenwhich pinion gear 410 can be positioned. In at least one embodiment,referring to FIG. 47, pinion spring 420 can be positioned intermediate,or compressed between, pinion gear 410 and first surface 424 of chamber422 such that spring 420 can bias pinion gear 410 against second surface426 of chamber 422. In certain embodiments, as a result, second surface426 can provide a datum against which pinion gear 410 can be positionedsuch that the teeth of pinion gear 410 can be aligned with the firstteeth 418 of drive shaft 400, at least until pinion gear 410 isdisengaged from drive shaft 400 as described in greater detail below.When pinion gear 410 is positioned against second surface 426, forexample, the teeth of pinion gear 410 can be operably engaged with bothdrive gear 408 and drive shaft 400. Accordingly, motor 402 can beoperably engaged with drive shaft 400 via gears 408 and 410 in order toadvance drive shaft 400 in direction D and/or retract drive shaft 400 indirection P, for example.

In various embodiments, referring to FIGS. 52 and 53, a surgicalinstrument can further include a knife bar assembly 450, for example,which can be operably coupled with drive shaft 400 such that, when driveshaft 400 is moved by motor 402 as described above, drive shaft 400 canmove knife bar assembly 450. In at least one embodiment, knife barassembly 450 can include a knife bar, or drive bar, 452 having aproximal end 454 connected to distal end 456 of drive shaft 400 eitherdirectly and/or by a coupling member (not illustrated). In at least onesuch embodiment, the surgical instrument can further include spine 475which can be configured to slidably receive and/or support drive bar 452within slot 477. In certain embodiments, knife bar assembly 450 canfurther include cutting instrument 460 operably engaged with distal end458 of drive bar 452 such that cutting instrument 460 can be moved in aproximal, distal, and/or any other suitable direction relative to endeffector 470. In various embodiments, knife bar assembly 450 can furtherinclude staple-driving sled 462 that can be advanced in a proximal,distal, and/or any other suitable direction by cutting instrument 460,for example, and can engage drivers 472 supporting staples 471 (FIG. 53)stored within staple cartridge 476. Similar to the above, end-effector470 can further include staple cartridge channel 478 which can beconfigured to retain and support staple cartridge 476. In any event, asurgical instrument can further include a spring 479 configured to biasanvil 474 into an open position and, in addition, a closure tube 480which can be configured to position and hold anvil 474 in a closedposition such that anvil 474 can deform staples 471 as they are deployedfrom staple cartridge 476.

In use, as described above, drive shaft 400 and drive bar 452 can beadvanced distally and retracted proximally by motor 402 in order toadvance and retract one, or both, of cutting member 460 and/or sled 462within end-effector 470. In the event, however, that one or more ofdrive shaft 400, drive bar 452, cutting instrument 460, sled 462, and/orany other portion of the drive, or firing, system becomes stuck, broken,or is otherwise unable to be sufficiently or fully retracted, a manualreturn system can be utilized to drive one or more of drive shaft 400,drive bar 452, and cutting instrument 460 proximally, for example. Incertain embodiments, motor 402 can be operably disengaged from driveshaft 400 before, during, and/or after the engagement of the returnsystem with drive shaft 400, for example. In various embodiments, motor402 can be disengaged from drive shaft 400 as the manual return systemis engaged with drive shaft 400. In at least one embodiment, such anarrangement may assure that the motor does not resist or prevent driveshaft 400, for example, from being driven distally by the return system.In certain embodiments, drive shaft 400, drive bar 452, cuttinginstrument 460, and/or sled 462 can be operably connected such that, ifa retraction force is applied to one or more of these members, theretraction force can be transmitted to one or more of the other memberssuch that they can be retracted together.

In various embodiments, referring to FIG. 44, a return system 500 caninclude a lever, or handle, 510 and a cam 520, wherein lever 510 can beconfigured to move cam 520. In at least one embodiment, referring toFIG. 48, lever 510 can be rotated in a first direction, represented byarrow 1, in order to move cam 520 between a first position (FIG. 48) anda second position (FIG. 49). In various embodiments, referring to FIG.44, lever 510 can be rotatably mounted to frame 404 by pivot pin 514,wherein pivot pin 514 can define an axis about which lever 510 can berotated. In at least one such embodiment, lever 510 can further includeaperture 516 which can be aligned with apertures 405 in frame 404 topermit pin 514 to be inserted therethrough. In various embodiments, pin514 and one or more apertures 405 can be configured such that there is asnug fit, or even press-fit, therebetween in order to prevent, or atleast inhibit, pin 514 from sliding out of apertures 405 and 516.Although not illustrated, one or more fasteners can be utilized toretain pin 514 within apertures 405 and 516. In any event, leveraperture 516 can be sized and configured such that there is sufficientclearance between the sidewalls of aperture 516 and pin 514 to permitsliding movement therebetween yet limit, or prevent, translationtherebetween. In at least one alternative embodiment, lever 510 can bemounted to pin 514 such that pin 514 can rotate with lever 510. Incertain embodiments, referring to FIG. 48 once again, lever 510 caninclude cam driver 512 extending therefrom which can be configured toengage at least a portion of cam 520, such as a drive surface, or drivepocket, 522 and rotate cam 520 in the first direction (indicated byarrow 1) when lever 510 is rotated in the first direction. In at leastone embodiment, referring once more to FIG. 44, cam 520 can be rotatablymounted to frame 404 by pin 514 which, similar to lever 510, can beinserted through cam aperture 524 and define an axis about which cam 520can be rotated.

In various embodiments, referring to FIG. 48, cam 520 can include firstcam surface 525 which can be positioned and configured to permit spring420 to bias gear 410 into engagement with drive shaft 400 when cam 520is in its first position as illustrated in FIG. 48. In at least oneembodiment, first cam surface 525 can be configured such that there isclearance between cam 520 and pinion gear 410 when cam 520 is in itsfirst position. As cam 520 is rotated into its second position by lever510, as described above and referring to FIG. 49, a portion of cam 520can contact pinion gear 410 and move pinion gear 410 out of engagementwith drive shaft 400. More particularly, in at least one embodiment, cam520 can include second cam surface 526 which, when in it comes intocontact with surface 413 of pinion gear 410, can force or move piniongear 410 toward first surface 424 in pinion gear chamber 422 and,correspondingly, compress spring 420. In various embodiments, camsurfaces 525 and 526 can define one or more arcuate and/or linearcontours, or profiles, which can permit relative sliding movementbetween cam 520 and pinion gear 410. In at least one such embodiment,cam surface 526, for example, can define a profile in which thedistance, or radius, between cam surface 526 and the axis of pin 514 cangradually increase between first cam surface 525 and stop point 527. Invarious embodiments, stop point 527 can define the end of second camsurface 526 and/or the furthest point on second cam surface 526 whichcontacts pinion gear 410. In certain embodiments, referring to FIGS. 48and 49, cam surface 526 can be at least partially defined by a firstradius of curvature R1 and a second radius of curvature R2, wherein R2can be larger than R1. In at least one embodiment, R1 and R2 can beselected such that the net difference between R1 and R2, or throw, canbe sufficient to displace pinion gear 410 such that pinion gear 410 isno longer operably engaged with drive shaft 400 when cam 520 is in itssecond position and/or stop point 527 of cam 520 is in contact withsurface 413 of pinion gear 410.

In various embodiments, when lever 510 is moved in the first direction(arrow 1) to rotate cam 520 between its first (FIG. 48) and second (FIG.49) positions by lever 510 as described above, lever 510 can moveretraction pawl assembly 530 into engagement with drive shaft 400.Referring to FIG. 48, which illustrates lever 510 before it is moved inthe first direction, retraction pawl assembly 530 is illustrated asbeing held out of engagement with drive shaft 400. More particularly,referring to FIG. 45, pawl 532 of pawl assembly 530 is illustrated asbeing held in a disengaged position by ledge 407 extending from frame404. In certain embodiments, still referring to FIG. 45, pawl 532 caninclude projection 534 extending therefrom which can be configured toslide along ledge 407. In at least one such embodiment, referring againto FIG. 48, pawl 532 can be slid in a proximal direction along ledge407, indicated by arrow A, when lever 510 is rotated in the firstdirection. At, or near, the same time as cam 520 is rotated into itssecond position as illustrated in FIG. 49, projection 534 can slide offof end 409 of ledge 407. In various embodiments, retraction pawlassembly 530 can further include pawl spring 536 which can be configureto bias pawl 532 into engagement with drive shaft 400 when projection534 has slid off of, or cleared, end 409 of ledge 407. In such anembodiment, the retraction pawl 532 can be engaged with drive shaft 400at the same time, or at least nearly the same time, as pinion gear 410is disengaged from drive shaft 400. In various alternative embodiments,ledge 407 can be configured such that projection 534 slides off of, orclears, ledge 407 prior to, and possibly just prior to, cam 520 beingfully rotated into its second position and pinion gear 410 beingcompletely disengaged from drive shaft 400. Alternatively, projection534 can slide off of, or clear, ledge 407 after, and possibly justafter, cam 520 is full rotated into its second position and pinion gear410 is disengaged from shaft 400. In any event, the disengagement of themotor 402 from drive shaft 400 and the engagement of pawl assembly 530with drive shaft 400 can allow drive shaft 400 to be retracted withoutresistance or interference from motor 402.

As described above, pawl 532 can be pivoted into engagement with driveshaft 400. In various embodiments, referring to FIGS. 49 and 50, pawlassembly 530 can further include pivot pin 538 which can be configuredto pivotably mount pawl 532 within slot 518 in lever 510. In at leastone embodiment, referring to FIG. 44, pivot pin 538 can be inserted intopin apertures 515 in lever 510 and aperture 533 in pawl 532 in order torotatably retain pawl 532 to lever 510 and define an axis about whichpawl 532 can rotate. In certain embodiments, referring to FIGS. 44 and48, pawl spring 536 can comprise a torsion spring, for example, whichcan include a central portion 537 positioned around pivot pin 538 and,in addition, legs 539 which can be configured to apply biasing, orcompressive, forces against pin 514, and/or any other suitable portionof lever 510, and pawl 532 such that pawl 532 can be biased toward driveshaft 400. In at least one embodiment, referring to FIG. 44, pawl 532can include channel 531 which can be configured to receive and/orcapture a leg 539 of spring 536 such that the leg 539 does not sliprelative to, or become operably disengaged from, pawl 532.

In any event, once pawl 532 has been slid off of, or has cleared, ledge407, lever 510, referring to FIG. 50, can be rotated in a seconddirection, indicated by arrow 2, which is opposite the first direction.When lever 510 is rotated in the second direction, lever 510 can pullpawl 532 distally in a direction indicated by arrow B. In variousembodiments, as illustrated in FIG. 50, lever 510 can pull pawl 532 suchthat it is slid over a plurality of second drive teeth 419 extendingfrom drive shaft 400. In at least the illustrated embodiment, seconddrive teeth 419 can be positioned on a different side of drive shaft 400than first drive teeth 418, although other various arrangements of thefirst and second drive teeth are envisioned which can place them on thesame side or opposite sides of the drive shaft. In certain embodiments,the first and second drive teeth may comprise one set of teeth, or firstand second portions of a set of teeth. In any event, pawl 532 caninclude one or more pawl teeth, such as pawl tooth 540, for example,which can be configured to slide over second drive teeth 419 when pawl532 is moved in direction B. In various embodiments, referring to FIG.50, pawl tooth 540 can include a first side 541 which can be configuredto slide over the angled, or beveled, sides 421 of second teeth 419without moving, or at least substantially moving, drive shaft 400 in aproximal and/or distal direction. When lever 510 is rotated in the firstdirection once again and pawl 532 is moved in a proximal direction asillustrated in FIG. 51, a second side 542 of pawl tooth 540 can engage aflat, or at least substantially flat, second side 423 of a second tooth419. Once side 542 of pawl tooth 540 is engaged with side 423 of asecond tooth 419, the proximal movement of pawl 532 can be transmittedto drive shaft 400 and move drive shaft 400 proximally. In embodimentswhere one or more of drive shaft 400, drive bar 452, cutting instrument460, and/or sled 462, for example, are stuck, a surgeon can apply aforce to lever 510 in order to dislodge the stuck component and retractdrive shaft 400, drive bar 452, cutting instrument 460, and/or sled 462in a proximal direction. In certain embodiments, only one stroke oflever 510 may be required to retract drive shaft 400 after pawl 532 hasbeen engaged with drive shaft 400. In other embodiments, however,multiple strokes may be required. In such embodiments, lever 510 may berepeatedly moved in the first and second directions in order to ratchetdrive shaft 400 proximally to a sufficient position.

In various embodiments, further to the above and referring to FIGS.48-51, the initial rotation of lever 510 in the first direction (arrow1) can set cam 520 in its second position and disengage pinion gear 410from drive shaft 400 as described above. When lever 510 is then rotatedin the second direction (arrow 2), however, cam 520 can remain in itssecond position. In at least one such embodiment, although cam driver512 extending from lever 510 may be configured to abut drive surface 522and move cam 520 from its first position (FIG. 48) into its secondposition (FIG. 49) as described above, cam driver 512 can be configuredsuch it can be rotated away from drive surface 522 when lever 510 isrotated in the second direction. In such embodiments, as a result, lever510 can thereafter be repeatedly moved in the first and seconddirections to retract drive shaft 400 while pinion gear 410 remainsdisengaged from drive shaft 400. In at least one such embodiment, oncecam 520 has been rotated into its second position, it may not bepossible to return cam 520 to its first position and/or move cam 520into any other position. As a result, cam 520 may permanently hold outpinion gear 410 out of engagement with drive shaft 400. In variouscircumstances, such a feature may be useful as it is often the case thata manual return, or ‘bail-out’, system does not need to be used unlessthe surgical cutting and stapling instrument is defective in somemanner. Such a feature could prevent the surgical instrument from beingreused unless the surgical instrument is examined and reset by aqualified technician, for example.

In certain embodiments, as described above, once a manual return, or‘bail-out’, system has been operably engaged with a drive system, themanual return system may not be disengageable from the drive systemand/or the drive system may otherwise be prevented from advancing adrive rod, for example, once again. In other various embodiments, themanual return system can be reset and the surgical instrument can beused once again. FIG. 54 is a diagram of a motor drive system and aportion of a manual return system of a surgical instrument in accordancewith such an embodiment of the present invention. In at least oneembodiment, the instrument can include drive shaft 600 which, similar tothe above, can be configured to advance and/or retract a cuttinginstrument and/or staple-driving sled within an end effector, forexample. Also similar to the above, as illustrated in FIG. 54, theinstrument can include a motor 602 configured to rotate a drive gear 608via a drive shaft 606. In various embodiments, drive gear 608 can beoperably engaged with an intermediate gear 610 such that rotation ofdrive shaft 606 can be transmitted to intermediate gear 610. Althoughgears 608 and 610 can comprise spur gears, or gears similar to the gearsillustrated in FIGS. 43-53, for example, gears 608 and 610 can compriseco-operating bevel gear portions, for example. Regardless of the type ofgears used, intermediate gear 610 can include a portion configured to beoperatively engaged with shaft gear 611. In various embodiments, shaftgear 611 can be freely rotated about shaft 612, although shaft 612 canbe closely received within an aperture in shaft gear 611 such that shaft612 can define an axis about which shaft gear 611 can be rotated. Incertain embodiments, shaft gear 611 can be mounted to shaft 612 suchthat the rotation of intermediate gear 610 can be transmitted to shaft612. As illustrated in FIG. 54, shaft 612 can be rotatably supported byframe 604 and/or any other suitable portion of the surgical instrument.

In various embodiments, further to the above, the drive system canfurther include motor crown gear 618 mounted to drive shaft 612 and/orshaft gear 611 such that the rotation of intermediate gear 610 can betransmitted to crown gear 618. In at least one embodiment, the drivesystem can further include spring 620 which can be configured to apply abiasing force to shaft gear 611, for example, such that one or more ofshaft gear 611, shaft 612, and crown gear 618 can be biased towardcentral gear 622. When it is desirable to have motor 602 operativelyengaged with drive shaft 600, for example, spring 620 can be permittedto push crown gear 618 into operative engagement with central gear 622.In at least one such embodiment, central gear 622 can include a crowngear portion 621 extending therefrom which can be configured tointermesh with crown gear 618. In embodiments where shaft gear 611 isslidably retained to shaft 612, central gear 622 can be fixedly mountedto shaft 612 and shaft 612 can be prevented, or at least inhibited, fromsliding relative to frame 604. In at least one such embodiment, centralgear 622 can be supported in position relative to drive shaft 600 byshaft 612.

Similar to the embodiments described above, circumstances may arise whenit may be desirable to engage a manual return system with drive shaft600. Also similar to the embodiments described above, it may also bedesirable to operably disconnect motor 602 from drive shaft 600 when themanual return system is engaged therewith. In various embodiments,referring to FIG. 55, a lever (not illustrated) of the manual returnmechanism can be moved, operated, or manipulated such that the lever canmove lever crown gear 624 into engagement with central gear 622, or atleast a crown gear portion 623 extending therefrom, and simultaneously,or at least substantially simultaneously, disengage motor crown gear 618from central gear 622. In at least one embodiment, lever crown gear 624can be slidably mounted to shaft portion 626 wherein, in at least onesuch embodiment, shaft portion 626 can comprise a portion of shaft 612.In various embodiments, lever crown gear 624 can include a cam surface,such as cam surface 640, for example, which can be engaged by a camextending from the manual retraction lever, for example, such that abiasing force can be applied to lever crown gear 624 via cam surface640. In at least one embodiment, push bar 628, which can also be mountedto lever crown gear 624 and/or slidably mounted to shaft 626, can beslid toward motor crown gear 618 until push bar 628 contacts a portionthereof. In certain embodiments, lever crown gear 624 and push bar 628can be configured such that crown gear 624 is engaged with central gear622 at, or near, the same time that crown gear 618 is pushed away fromcentral gear 622.

In various embodiments, further to the above, the surgical instrumentcan further include a catch, or lock, 630 which can be configured tocapture motor crown gear 618 when it is disengaged from crown gear 622and, in addition, hold crown gear 618 in place as the manual returnlever is used to drive crown gear 624 and central gear 622. In at leastone such embodiment, lock 630 can include a hook 629, for example, whichcan be lifted upwardly when crown gear 618, or a rim 619 surroundingcrown gear 618, contacts hook 629. In certain embodiments, hook 629 cansnap over rim 619 owing to a biasing force applied to lock 630 by returnspring 632. At some point, a surgeon may desire to re-engage motor 602with drive shaft 600 and may push downwardly, for example, on end 631 oflock 630 such that lock 630 can pivot and, as a result, lift hook 629upwardly and out of engagement with crown gear 618. At such point,spring 620 may expand and bias crown gear 618 into engagement withcentral gear 622 once again. Correspondingly, spring 620 may also applya sufficient force to crown gear 618 in order to disengage or push crowngear 624 away from central gear 622 via push bar 628.

In various embodiments, a surgical instrument can include a drive systemand a manual return mechanism as illustrated in FIGS. 61-67, forexample. Referring to FIGS. 61 and 62, the drive system can include amotor 902 configured to rotate motor drive shaft 906 and motor drivegear 908. In certain embodiments, the drive system can further includepinion gear 910 which can be selectively engaged with drive shaft 900 asdescribed in greater detail below. In at least one embodiment, piniongear 910 can be rotatably mounted to swing arm 931 via pin 912 and oneor more pin apertures 916 such that, when swing arm 931 is in a firstposition as illustrated in FIG. 62, the teeth of pinion gear 910 can bemeshingly engaged with the teeth of drive gear 908 and, in addition,first teeth 918 on drive shaft 900. When swing arm 931 is in its firstposition, as a result, motor 902 can be configured to rotate drive gear908 in a first direction so as to move drive shaft 900 in a distaldirection along axis 903, for example, and, at other times, rotate drivegear 908 in a second direction so as to retract drive shaft 900proximally, for example. In various embodiments, swing arm 931 can beselectively held in its first position and, in some embodiments, swingarm 931 can be releasably held in its first position by cam 1020. In atleast one such embodiment, swing arm 931 can include a retention slot939 configured to receive a least a portion of cam 1020 when cam 1020 isalso in a first position as described in greater detail below.

Referring again to FIGS. 61-67, manual return mechanism 1000 can beselectively engaged with drive shaft 900 in order to manually retractdrive shaft 900. In various embodiments, manual return mechanism 1000can be similar in design and operation to manual return mechanism 500,for example, wherein manual return mechanism 1000 can include lever 1010and pawl 1032 which can be configured to engage second teeth 919 ondrive shaft 900 and retract drive shaft 900 proximally. A detaileddisclosure of manual return mechanism 500, among others, is providedthroughout the present application and the reader will appreciate thatsuch disclosure can be applicable to the design and operation of manualreturn mechanism 1000. In at least one embodiment, lever 1010 can berotated in a first direction from a first position, illustrated in FIG.62, into a second position, illustrated in FIG. 63. When lever 1010 ismoved in its first direction, lever 1010 can move pawl 1032 intoengagement with second teeth 919 and, in addition, move cam 1020 betweenits first position, illustrated in FIG. 62, and a second position,illustrated in FIG. 63. In at least one embodiment, similar to theabove, cam 1020 can include a drive surface 1022, for example, which canbe contacted by a cam driver 1012, for example, extending from lever1010 in order to rotate cam 1020 into its second position about an axisdefined by pin 1014. When cam 1020 is rotated into its second position,cam 1020 can be disengaged from retention slot 939 in swing arm 931.More particularly, in at least one embodiment, cam 1020 can include afirst portion 1025 which can be sized and configured to be receivedwithin retention slot 939 when cam 1020 is in its first positionwherein, when lever 1010 is rotated in its first direction, first camportion 1025 can be rotated out of retention slot 939. As cam 1020 ismoved into its second position, second cam portion 1027 can bepositioned over, but not positioned within, retention slot 939. In atleast one embodiment, second cam portion 1027 may be positioned withinretention slot 939 but may not be able to hold swing arm 931 inposition.

In various embodiments, swing arm 931 can be rotatably mounted to frame904 such that, when cam 1020 is sufficiently disengaged from retentionslot 939, swing arm 931 can be pivoted in order to move pinion gear 910away from and out of engagement with drive shaft 900 and/or drive gear908. In at least one embodiment, referring to FIGS. 63, 65, and 67,proximal end 933 of swing arm 931 can be pivotably mounted to frame 904via a hinge 935. In use, as outlined above, swing arm 931 can be held inits first position by cam 1020 until lever 1010 is utilized to disengagecam 1020 from swing arm 931 such that swing arm 931 can be moved into asecond position. In at least one embodiment, referring to FIG. 34,manual return mechanism 1000 can further include at least one spring,such as spring 920, for example, which can be configured to bias swingarm 931 into its second position. Spring 920 can be configured such thatit is compressed intermediate swing arm 931 and frame 904, for example,when swing arm 931 is in its first position, wherein spring 920 can bepermitted to expand and move swing arm 931 into its second position whencam 1020 is moved into its second position. In at least one embodiment,the range of motion of swing arm 931 can be confined. In someembodiments, the proximal end 933 of swing arm 931 can further includeone or more stop surfaces, such as stop surface 937, for example, whichcan be configured to engage frame 904, for example, in order to limitthe range of motion of swing arm 931. In any event, once swing arm 931has been moved into its second position, pinion gear 910 may no longerbe operably engaged with drive gear 908 and/or first teeth 918 of driveshaft 900. In such circumstances, the rotation of drive gear 908 bymotor 902 may not be transmitted to drive shaft 900 and the retractionof drive shaft 900 by lever 1010 and pawl 1032 may be performed withoutinterference, or at least substantial interference, from motor 902.

In various embodiments, further to the above, the movement of lever 1010in its first direction can both engage manual return mechanism 1000 withdrive shaft 900 and operably disengage motor 902 from drive shaft 900.After being moved in its first direction, lever 1010 can be rotated in asecond direction to return lever 1010 to its starting position wherein,similar to the above, lever 1010 can be rotated away from cam 1020 suchthat cam 1020 is left in its second position. At such point, lever 1010can be repeatedly ratcheted in its first and second directions in orderto suitably retract drive shaft 900. In at least one embodiment, manualreturn mechanism 1000 can be configured such that a surgeon, or anotheroperator of the instrument, is not afforded the opportunity to reset theinstrument and, as a result, motor 902 cannot be utilized once again tomove drive shaft 900. In at least one other embodiment, manual returnmechanism 1000 can be reset by pushing swing arm 1031 back into itsfirst position and rotating cam 1020 into its first position such thatfirst cam portion 1025 is engaged with retention slot 939 once again.

In various embodiments, referring to FIGS. 56-58, a surgical instrumentcan include a rotatable drive shaft and a manual return mechanismconfigured to rotate the drive shaft. In at least one embodiment,referring to FIG. 56, rotatable drive shaft 700 can be rotatablysupported in apertures 714 and 716 of frame 704, for example. In certainembodiments, the surgical instrument can further include a drive systemconfigured to rotate drive shaft 700, wherein the drive system cancomprise a drive gear 708, a motor 702 for rotating drive gear 708, anda gear box 701 which can be configured to provide a gear reductionand/or otherwise allow motor 702 and drive gear 708 to rotate atdifferent speeds. The surgical instrument can further include a piniongear 710 which, when positioned in a first position as illustrated inFIG. 56, can be configured to transmit the rotational motion of drivegear 708 to drive shaft 700. In various embodiments, drive shaft 700 caninclude a spline portion 718 which can comprise one or more projectionsand/or one or more recesses which can be closely received by thesidewalls of an aperture (not illustrated) extending through pinion gear710. In at least one such embodiment, the perimeter of the pinion gearaperture can be configured such that it matches, or at leastsubstantially matches, the perimeter of spline portion 718. Owing to theco-operating features of the pinion gear aperture and spline portion718, motor 702 can be operably engaged with drive shaft 700 such thatthe rotational motion of drive gear 708 can be transmitted to driveshaft 700. When drive shaft 700 is rotated in a first direction, driveshaft 700 can be configured to advance drive nut 756, and knife barassembly 750 attached thereto, along drive shaft 700. More particularly,in at least one embodiment, the outer surface of drive shaft 700 cancomprise a helical drive thread which, when rotated relative to drivenut 756, can be configured to convert the rotational movement of driveshaft 700 to the translational movement of drive nut 756 such that drivenut 756 is advanced along shaft axis 703. Correspondingly, when driveshaft 700 is rotated in an opposite direction, the helical thread canretract drive nut 756. As illustrated in FIG. 56, the proximal end 754of knife bar 752 can be attached to and/or otherwise suitably engagedwith drive nut 756 such that, when drive nut 756 is advanced distallyand/or retracted proximally by drive shaft 700, knife bar 752 can bemoved along with drive nut 756 in order to move a cutting member and/orstaple sled associated therewith within an end effector.

In use, as outlined above, motor 702 can rotate drive shaft 700 in afirst direction in order to advance knife bar assembly 750 and, inaddition, rotate drive shaft 700 in a second direction in order toretract knife bar assembly 750. In the event, however, that motor 702becomes inoperable and/or knife bar assembly 750 becomes stuck, forexample, manual retraction mechanism 800 can be operably engaged withdrive shaft 700 in order to rotate drive shaft 700 in its second, orretraction, direction. In various embodiments, referring to FIGS. 56 and57, a surgeon, or another operator of the instrument, can pull yoke 715out of engagement with pinion gear 710 such that pinion gear 710 can bedisplaced, or slid, between its first position in which it is engagedwith drive gear 708 and spline portion 718 and a second position inwhich it is engaged with spline portion 718 and lever 810. In at leastone embodiment, pinion gear 710 can be moved from its first position, asillustrated in FIG. 56, into its second position, as illustrated in FIG.57, by spring 718 after yoke 715 has been disengaged from collar 713 ofpinion gear 710. In certain embodiments, referring now to FIG. 59, yoke715 can include handle 717 which can be configured to be grasped by thesurgeon such that one or more projections, or tines, 709 extending fromyoke 715 can be disengaged from recess 707 defined within collar 713. Inany event, once pinion gear 710 has been moved into its second position,as illustrated in FIG. 57, pinion gear 710 can be operably engaged withretraction lever 810. In certain embodiments, spring 710 can bias piniongear 710 against retraction lever 710 such that ratchet face 719 onpinion gear 710 is operably engaged with ratchet face 832 on lever 810.

In various embodiments, further to the above, pinion gear 710 can bemoved out of engagement with drive gear 708 at the same time as piniongear 710 is moved into engagement with lever 810. In certainembodiments, pinion gear 710 can be moved out of engagement with drivegear 708 before pinion gear 710 is moved into engagement with lever 810.In any event, in at least one embodiment, the rotation of lever 810 canbe transmitted to pinion gear 710 via the co-operating ratchet teeth onratchet faces 719 and 832, wherein the rotation of pinion gear 710 canbe transmitted to drive shaft 700 via spline portion 712. In certainembodiments, only one rotation, or less than one rotation, of lever 810may be required to sufficiently retract drive shaft 700 although, inother embodiments, more than one rotation of lever 810 may be required.In various embodiments, referring to FIG. 58, the ratchet faces of lever810 and pinion gear 710 can be configured to allow lever 810 to berotated in a second direction, i.e., a direction opposite the firstdirection, in order to return lever 810 to its starting position suchthat lever 810 can be rotated in its first direction once again. In atleast one embodiment, pinion gear 710 and/or drive shaft 700 can be heldin position while lever 810 is ratcheted back into its startingposition, for example, so as to prevent, or at least inhibit, driveshaft 700 from simply moving back and forth with lever 810. In at leastone such embodiment, referring to FIG. 58, the rotation of lever 810 inits second direction can displace pinion gear 710 into at least partialengagement with drive gear 708 such that drive gear 708, gear box 701,and motor 702 can hold pinion gear 710 in position while lever 810 isrotated in its second direction. In certain embodiments, the gear ratiosbetween pinion gear 710 and drive gear 708, and/or within gear box 701,can be such that the rotation of pinion gear 710 is prevented, or atleast inhibited, absent the application of a significant mechanicaladvantage and/or force to lever 810, which may not occur under mostcircumstances.

In various embodiments, further to the above, the lever 810 can beratcheted in its first and second directions as many times as needed inorder to rotate drive shaft 700 in its second direction such that knifeassembly 750 is sufficiently retracted. In at least one embodiment,manual retraction mechanism 800 can be configured such that pinion gear710 cannot be returned to its first position after being moved into itssecond position. In such embodiments, motor 702 cannot be used to rotatedrive shaft 900 once again. In certain other embodiments, pinion gear710 can be returned to its first position and yoke 715 can be re-engagedwith collar 713 such that pinion gear 710 can be held in operativeengagement with drive gear 708 and, correspondingly, motor 702.

In various embodiments, as described above, the operation, or actuation,of a manual retraction lever can operably disengage a motor from a driveshaft such that the motor does not resist or impede the movement of themanual retraction lever. In several such embodiments, the operation ofthe retraction lever can mechanically decouple the motor from the driveshaft. Such embodiments may provide an advantage in that, even if themotor continues to rotate, the rotation of the motor cannot betransmitted to the drive shaft. In certain embodiments, the operation ofa manual retraction lever can electrically decouple the motor from apower source. Such embodiments may provide an advantage in that themotor cannot rotate without power from the battery regardless of whetherthe motor and the drive shaft have been mechanically decoupled. In someembodiments, the operation of a manual retraction lever can cause theactuation of an electro-mechanical device, such as a solenoid, forexample, which can electrically decouple, mechanically decouple, and/orlock a drive shaft in position. In various embodiments, a manualretraction system can include a mechanical decoupling arrangement, anelectrical decoupling arrangement, and/or an electro-mechanicaldecoupling arrangement. In at least one embodiment, referring to circuit1100 illustrated in FIG. 60, a surgical instrument can include a battery1101, a motor 1102, and one or more switches, such as bail-out, ormanual return, lever switch 1103, for example, which can be configuredto electrically couple/decouple battery 1101 and motor 1102. In variousembodiments, switch 1103 can comprise a single pole-single throw switch,and/or any other suitable switch, wherein the operation of a bail-out,or manual return lever, such as lever 810, for example, can open theswitch 1103 and electrically decouple battery 1101 from motor 1102. Incertain embodiments, switch 1103 can comprise a single pole-double throwswitch as illustrated in FIG. 60. In at least one such embodiment, theoperation of the manual return lever can manipulate the switch 1103between a first condition in which contacts 1 and 2 are in electricalcommunication with one another such that current can flow to motor 1102and a second condition in which contact 1 is connected to contact 3(which may be grounded) and, as a result, current cannot flow frombattery 1101 to motor 1102. In various embodiments, the initialoperation of the manual return lever can manipulate switch 1103 betweenits first and second conditions, wherein, in at least one embodiment,switch 1103 cannot be closed, or reset, after it has been opened and, asa result, motor 1102 cannot be used to move the drive shaft of thesurgical instrument once again. In other embodiments, however, switch1103 can be reset, or closed, and power can be supplied to motor 1102from battery 1101 once again. In at least one such embodiment, althoughnot illustrated, the drive shaft, and/or a knife assembly engaged withthe drive shaft, can reset the switch after it has been retracted asufficient distance. Although mechanical switches can be utilized invarious embodiments, solid state or electro-mechanical switches, aprocessor-based controller, and sensor systems can be utilized to detectthe movement of the manual retraction lever.

Referring once again to circuit 1100, although only one manual returnlever switch 1103 is illustrated in FIG. 60, two or more switches can beutilized. In at least one such embodiment, although not illustrated,such switches can provide for a redundant system. In variousembodiments, circuit 1100 can further include a clamp switch 1104 whichcan be configured to detect whether the anvil of an end effector hasbeen closed. More particularly, in at least one embodiment, switch 1104can be configured such that it is in a normally-open condition whereincurrent cannot flow to motor 1162 unless switch 1104 has been closed bythe anvil. In various embodiments, circuit 1100 can further include aswitch arrangement 1106 which can be utilized to detect (i) whether astaple cartridge positioned within an end effector has beenpreviously-used and/or (ii) information regarding the position of acutting member within the end effector. In at least one embodiment,switch arrangement 1106 can include a spent cartridge switch 1108 whichis in a normally-closed condition, i.e., until the staple cartridge hasbeen at least partially expended after which switch 1108 can be in anormally-open condition. In certain embodiments, switch 1108 can beopened by a cutting member when it reaches the end of its stroke withinan end effector. When spent cartridge switch 1108 is in a closedcondition, most of the current can flow directly from clamp switch 1104to fire trigger switch 1110 through the low-resistance conduction pathof the switch 1108, for example. When spent cartridge switch 1108 is inan open condition, the battery current flows through a networkcomprising parallel-connected resistors R1, R2, R3, R4, and R5, forexample. The resistance of the resistor network may be sufficiently highto substantially lower the current flowing to motor 1102. In suchcircumstances, the lowered current can be insufficient to operate motor1102 but can still provide a sufficient current which can be detected.In various embodiments, the lowered current can be evaluated by amicroprocessor (not illustrated) to determine the current level throughthe various resistors and, in view of such information and/or otherprovided information, determine which type of staple cartridge ispresent in the end effector. Various embodiments are disclosed incommonly-owned, U.S. patent application Ser. No. 12/235,782, entitledMOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT, which was filed on Sep. 23,2008, now U.S. Pat. No. 8,210,411, the entire disclosure of which ishereby incorporated by reference herein.

In various embodiments, further to the above, circuit 1100 can furtherinclude a firing trigger switch 1110 which can switched from anormally-open condition to a closed condition when a firing trigger isactuated to fire, or deploy, the staples. In at least one embodiment,such a firing trigger can comprise a lever, which can be squeezed by thesurgeon, and/or any other suitable trigger, such as a push-buttontrigger, for example. In any event, contacts 1 and 2 of switch 1110 canbe placed in electrical communication with one another when the firingtrigger is actuated such that the current can flow though motor 1102. Incertain embodiments, though, circuit 1100 can further include motordirection switch 1112 which can be configured to change the polarity ofthe voltage applied to motor 1102 and, as a result, change the directionin which motor 1102 is rotated. As illustrated in FIG. 60, contacts 1and 3 of motor direction switch 1112 can be in electrical communicationwith one another to cause motor 1102 to rotate in such a direction so asto advance a cutting member and/or staple sled within an end effector.In order to retract the cutting member and/or staple sled, motordirection switch 1112 can be reconfigured such that contacts 1 and 2 arein electrical communication with one another and the polarity of thevoltage applied to motor 1102 can be reversed.

The various embodiments of the present invention have been describedabove in connection with cutting-type surgical instruments. It should benoted, however, that in other embodiments, the inventive surgicalinstrument disclosed herein need not be a cutting-type surgicalinstrument. For example, it could be a non-cutting endoscopicinstrument, a grasper, a stapler, a clip applier, an access device, adrug/gene therapy delivery device, an energy device using ultrasound,RF, laser, etc. Although the present invention has been described hereinin connection with certain disclosed embodiments, many modifications andvariations to those embodiments may be implemented. For example,different types of end effectors may be employed. Also, where materialsare disclosed for certain components, other materials may be used. Theforegoing description and following claims are intended to cover allsuch modification and variations.

Furthermore, the present invention has been discussed in terms ofendoscopic procedures and apparatuses. However, use herein of terms suchas “endoscopic” should not be construed to limit the present inventionto a surgical stapling and severing instrument for use only inconjunction with an endoscopic tube (i.e., trocar). On the contrary, itis believed that the present invention may find use in any procedurewhere access is limited to a small incision, including but not limitedto laparoscopic procedures, as well as open procedures. Moreover, theunique and novel aspects of the various staple cartridge embodiments ofthe present invention may find utility when used in connection withother forms of stapling apparatuses without departing from the spiritand scope of the present invention.

Further to the above, the various staple cartridges disclosed herein canbe disposable. In at least one embodiment, an expended staple cartridge,or an at least partially expended staple cartridge, can be removed froma surgical stapler and replaced with another staple cartridge. In othervarious embodiments, the staple cartridge may not be removable and/orreplaceable during the ordinary use of the surgical instrument but, insome circumstances, may be replaceable while and/or after the surgicalstapler is reconditioned as described in greater detail below. Invarious embodiments, the staple cartridge can be part of a disposableloading unit or end-effector which can further include a staplecartridge carrier, anvil, cutting member, and/or staple driver. In atleast one such embodiment, the entire, or at least a portion of, thedisposable loading unit or end-effector can be detachably connected to asurgical instrument and can be configured to be replaced.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

Preferably, the invention described herein will be processed beforesurgery. First, a new or used instrument is obtained and if necessarycleaned. The instrument can then be sterilized. In one sterilizationtechnique, the instrument is placed in a closed and sealed container,such as a plastic or TYVEK bag. The container and instrument are thenplaced in a field of radiation that can penetrate the container, such asgamma radiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.

1. A surgical fastening apparatus, comprising: an end effector,comprising: a first jaw; a second jaw, wherein said first jaw is movablerelative to said second jaw between an open position and a closedposition; and a fastener cartridge comprising a plurality of fastenersremovably stored therein; a handle, comprising: an electric motor; anactuator configured to operate said electric motor; and a batteryconfigured to supply power to said electric motor; a firing member,wherein said motor is configured to impart a firing motion to saidfiring member to eject said fasteners from said fastener cartridge; anda manually-driven bailout mechanism configured to retract said firingmember and to electrically disconnect said battery from said motor whensaid bailout mechanism is moved from an unused position to a usedposition.
 2. The surgical fastening apparatus of claim 1, wherein saidbattery cannot apply a voltage potential to said motor when said bailoutmechanism has electrically disconnected said battery from said motor. 3.The surgical fastening apparatus of claim 1, further comprising a switchconfigurable in an open condition and a closed condition, wherein saidbailout mechanism is configured to move said switch between said closedcondition and said open condition when said bailout mechanism is movedfrom said unused position to said used position.
 4. The surgicalfastening apparatus of claim 3, wherein said switch is not resettableback into said closed condition after it has been moved into said opencondition.
 5. The surgical fastening apparatus of claim 3, wherein saidswitch is resettable back into said closed condition when said bailoutmechanism is returned to said unused position.
 6. The surgical fasteningapparatus of claim 1, wherein at least a portion of said bailoutmechanism is not resettable back into said unused position after saidbailout mechanism has been moved into said used position.
 7. Thesurgical fastening apparatus of claim 1, wherein said bailout mechanismis resettable back into said unused position after said bailoutmechanism has been moved into said used position.
 8. The surgicalfastening apparatus of claim 1, wherein said fastener cartridge issupported by said second jaw.
 9. The surgical fastening apparatus ofclaim 1, wherein said fastener cartridge is removably attached to saidend effector.
 10. The surgical fastening apparatus of claim 1, furthercomprising a shaft extending from said handle, wherein said end effectoris engaged with and supported by said shaft.
 11. The surgical fasteningapparatus of claim 1, wherein said bailout mechanism is configured toelectrically decouple said battery from said motor and mechanicallydecouple said motor from said firing member when said bailout mechanismis moved from said unused position to said used position.
 12. Thesurgical fastening apparatus of claim 1, wherein at least a portion ofsaid bailout mechanism is configured to permanently block said motorfrom driving said firing member after said bailout mechanism has beenmoved from said unused position to said used position.
 13. A surgicalfastening apparatus, comprising: an end effector, comprising: a firstjaw; a second jaw, wherein said first jaw is movable relative to saidsecond jaw between an open position and a closed position; and afastener cartridge comprising a plurality of fasteners removably storedtherein; a handle, comprising: an electric motor; a battery configuredto supply power to said electric motor; and an electrical circuitconfigured to electrically connect said battery to said electric motorto supply power to said electric motor; a firing member, wherein saidmotor is configured to impart a firing motion to said firing member toeject said fasteners from said fastener cartridge; and a retractionsystem configured to selectively interrupt said electrical circuit toprevent said battery from supplying power to said motor, wherein saidretraction system comprises a driver configured to retract said firingmember.
 14. The surgical fastening apparatus of claim 13, wherein saidelectrical circuit comprises a switch configurable in an open conditionand a closed condition, wherein said return driver is configured to movesaid switch between said closed condition and said open condition whensaid return driver is moved from an unactuated configuration to anactuated configuration to interrupt said electrical circuit.
 15. Thesurgical fastening apparatus of claim 14, wherein said switch is notresettable back into said closed condition after it has been moved intosaid open condition.
 16. The surgical fastening apparatus of claim 13,wherein said return driver is also configured to mechanically decouplesaid motor from said firing member when said retraction driverinterrupts said electrical circuit.
 17. A surgical instrument,comprising: a handle, comprising: an electric motor; and a power sourceconfigured to supply power to said electric motor; a firing member,wherein said motor is configured to impart a firing motion to saidfiring member; and means for de-energizing said electric motor whenimparting a retraction motion to said firing member. 18-24. (canceled)